Jill CLayburgh is a woman's woman. She is every woman's idea of what she would like her best friend to be. She is comfortable, friendly, open, intimate, straight, smart, funny, confiding . . . She doesn't mind laughing at herself, exposing her vulnerabilities, empathizing.

All this is not to say that she isn't attractive. She isn't beautiful in the classic sense, but she has such an appealing face and such an inner glow that she becomes prettier as she talks. What keeps her from being really beautiful is lack of defination about her features, a fuzziness which makes her seem unclear as a face, compared to someone like, say, Jane FOnda, who, though not perfectly beautiful either, has such clear strong features you think she is.

Clayburgh doesn't act like she thinks she is beautiful. Rather she acts confident and at ease with what good looks she does possess.

She is not the kind of woman other women are necessarily jealous of, regardless of her talent, her success, her looks, because she's not the kind of woman who goes after other women's men. You get the feeling that if she's your friend she's not going to go after your man. Instead, because she knows how much it hurts, she'll listen for hours to your problems and share hers with you, hashing tirelessly over relationships on the phone until you've both got cauliflower ears, then be right back at it with you next morning. She's the kind of woman you want to have around when you break up with the man you love.

This could be, in part, because she has been through so much herself. She lived with Al Pacino for five years before he walked out on her with little warning, much like Erica's experience in "An Unmarried Woman" where she loses her husband of 16 years.

Clayburgh admits that probably the most painful moment in her life was when Pacino left her. "I went through it all," she says, "self-loathing, loathing him, pain, anger, fear.

"I still remember my song with Al now," she says with a slightly wistful shrug. "'It's Too Late, Baby.'"

And now she can say with a believable casualness "we're still friends; we see each other now and then." And she says, defensively, that she is probably the only person alive who really liked Pacino's negatively reviewed film, "Bobby Deerfield."

There is a certain determination in her voice, however, when she says, "I'd rather not live with an actor again. It's too hard."

Part of the reason her breakup with Pacino was so hard "obviously had to do with fact that he was just becoming a big success and I hadn't made it yet." (Pacino had just finished "The Godfather," the role that sent him to stardom.)

Ironically, it is Clayburgh who is the big star now and Pacino's career which is on the decline.

So you'd think Jill Clayburg would be on top of the world right now.

And she is. Sort of.

Her latest movie, "An Unmarried Woman," is a huge success and the reviews have been spectacular. She is in constant demand and has been since her last two successes, "Silver Streak" and "Semi-Tough." She has become, after 15 years of hard work as an actress both on the stage and in movies, a major figure in the film industry. Hundreds of scripts have been pouring in and she says she sometimes reads 10 a day. But so far, she hasn't found anything since "An Unmarried Woman" that she likes, or thinks is right for her. So for the last 11 months Jill Clayburgh has not worked.

And she's worried.

"It's like, what movie can I do now," she says, "after 'An Unmarried Woman?' Yet I don't want to get into that syndrome of I'll never work again.' But you do something just because you want to work and everybody says, 'Why did you do that horrible movie?" Well, you don't think it's going to be horrible on me to make a wonderful movie with a wonderful director and be wonderful. And that kind of pressure keeps you from taking risks. I guess," she says. "it would probably be more valuable for me to fail. I would grow more. And it would be better than just sitting wround and repeating myself. I could wait five years before I found a part as good as this. And I would really hate to get into that. It's a real problem."

It's not that big a problem though. And anyway, Jill Clayburgh has had enough problems in her life that she can handle this one.

She takes a large bite out of her croissant, munches pensively for a moment and then laughs. "I felt once this movie came out," she says, "that I would, as Woody ALlen would say, meet a higher class of people. It's just a question of time. Right now a lot of good directors are tied up."

She thinks, though, that she's had just about enough vacation. "For the first six or eight months," she says, "I was very happy . I went skiing, I read books, I listened to music, I talked to my girl friends on the phone. I talk a lot on the phone. I cooked a lot. I stayed home a lot - though you wouldn't knowit judging from the mess in my apartment. I jog about an hour and a half a day or to go to the gym, I waste a lot of time talking to David (playwright David Rabe, the man she lives with) and I unseccessfully tried to learn tennis. It's only been in the last month or so that I've been a little buggy."

"But you know," she says, "I had done two pictures in a row and I was really exhausted. I hadn't spent time with my own life. I needed to sleep, to see my friends and most importantly, to spend time with David."

When Jill Clayburgh walks into the lobby of the Sherry Netherlands hotel for an interview no one recognizes her. In the dining room, the maitre d'hotel refuses a larger table, insisting that "two women always mess up tables," showing instead a small cramped table in the corner, and only after being told it is an interview-breakfast does he relent and agree to a large one. Still no one recognizes Jill Clayburgh.

She is dressed simply in the plaid shirt, a vest, curduroy pants and a suede jacket. Her hair tousled an vaguely curled. She wears almost no makeup. Very un-moviestar-like. No swishing in with minks and dark glasses, no entourage, no jewels, no affectation. Just Jill.

And she will say with total simplicity, "I'm not a personality. I don't go on talk shows. I don't shine. It's not what I do. It's not what I'm interested in. I didn't want this publicity, but the movie is so good I just had to do it."

And she says she certainly doesn't think of herself as being famous. "I'm always shocked when people on answering services know how to spell my name."

She settles into a banquette and orders croissants right away, joking about how articles about her always insist she is dieting.

She will be 34 in a few weeks and she has never been married. Even now that she is in love with - and has been living with for nearly three years - David Rabe ("Streamers") she is still ambivalent about marriage.

"There was a long period of time when I really wanted to get married," she says. "Now I just don't see what it would do for me. I just don't get it I'm not against it. I have my own name, my own money, no children and I understand what my commitment is. What would marrying bring me that I don't have now? And I've certainly gotten over wanting to be married for my parent's sake. David's parent still don't like the fact that we're not married. And the publicity just drives them crazy. But I don't know. There's something about people wanting you to be accepted. Well, I don't want to be accepted. Being married is like being a huge tree with all the sap sucked out of it. I feel like if you're married you're like a dead branch. And once you get married nobody cares anymore. They accept you. You stop being interesting. Look at Farrah Fawcett-Majors. I don't think she could have gone through all this kind of publicity if she hadn't been married. It probtected her. But it also made her king of boring."

Still, Clayburgh does admit that it doesn't matter as much in the public's eye whether actresses are married or not since, as she says, "actresses are the closets things to whores in our society. As an actress it's more unusual to be married. So I suppose," she says, her face lighting up with a smile, "I'm doing the less interesting thing by living with David."

Nevertheless, not wanting to be married, or not thinking she does, poses another problem for Clayburgh. Which is the problem most women in their 30s face if they've never had children. Whether or not to have a baby.

"I really want children," she says. "I don't want to wait. I like having them around."

Every three weeks Clayburgh and Rabe have his 6-year-old son, Jason, by a first marriage, come to stay with them.

"When children are around you're not thinking about yourself all the time," she says. "You don't think of your work, your life, your problems. You have to button their pants. It's something outside yourself."

She has thought of the problems of having children and a career. "It's easier for me than for most working women," she says. "If you're acting in movies you can take nine months off and then you can always take the baby to the set. It does get harder when the child is in the school. But I don't want to have a child brought up with nursemaids. I grew up that way. The thought of having the nurse bring the child in to kiss the parents good night doesn't interest me."

here was a period, before Clayburgh got involved with Rabe, she says, where she was terribly lonely. "For a while there," she says, "I was desperate to have a baby, hysterical I wasn't going to have one. But, I finally realized that I wanted it to solve my problems. I was alone. I wanted something to care for and nurture but that something was me. The baby was me. I wanted to have myself. Now I just know I want one."

"A friend of mine," she muses, "had a baby recently and it nearly drove me crazy."

"But," she says, cheerily, coming out of her slump, "having a baby is so imminant for me that I really can't talk about it."

This bring us back to marriage again. "If I had a baby would I get married? Yeah. I couldn't go through that kind of hassle. I don't want any attention paid to my personal life, really. Oh, who knows," she says with no little frustration, "part of it is that we were supposed to get married and have children."

If Clayburgh is ambivalent about marriage and cildren, if she changes her mind about both every other moment, she is certainly no different from at lot of other women, particularly those with careers. And she is equally ambivalent about growing older.

"I think about getting old and being an actress," she says. "I do think in this society that people don't think lines on a woman's face are good. On men they are."

She pulls at her face, grimaces, grabbing her cheeks with each hand and stretching them back so that her skin is smooth. "I do this for David and ask him if he thinks I look younger. He says it's great until I try to talk." She chucks herself under her chin searching, as only a woman over 30 will do, for that telltale first slackening of skin. "I have absolutely no qualms about having my face lifted," she says, still patting her face, looking for more droops."I'm ready rigt now."

"I don't know," she says. "I don't think there are that many parts for older women. So Shirley MacLaine and Anne Bancroft did a movie. Big deal. That's just one movie. I don't see very many people making it past 40. But I do think there's hope. The years ago I would have been washed up at 30. I can always go back to the theater or grow vegetables, though," she says with a wry smile. "What I really don't want to do is hang on to youth. That's terrible. I'm not frightened about it," she says. "It's just that I never though about age before."

What she has though about though, thinks more and more about is the clock ticking away on her childbearing years. "I have worried about age as far as having children," she says. "I used to think I'd have to have a baby before I was 35. But now that's not valid any more with all the tests. Still, it makes me really mad. And I also worried about not being a real woman, without having a baby . I hate to live in fear of that."

Regardless of her ambivalences, Clayburgh thinks she is better shape now than she's ever been. "I'm more grounded and I have more fun," she says. "I'm less crazed, less unhappy. I'm happier and that makes me more attractive. At the moment I'm successful. And it's hard to seperate the two. I'm glad, too, that I'm this age and successful. I know a lot more than I did when I was younger. Although," she says with a small frown, "I do get crazy sometimes. Really lose my marbles."

Jill Clayburgh grew up in New York City, the daughter of a well-to-do book cloth manufacturer. Her mother David Merrick's secretary, hence her interests in the theater. Her childhood was an unhappy one. She went to Bearly School for Girls and Sarah Lawrence, but she never got along with her parents. She began therapy at an early age. She had severe emotional problems.

"I was very rebellious as a teenager," she says, "aside from having an unhappy, neurotic childhood. But I just can't go into it. I think I had a lot of energy and undirected need so I just kind of rebelled in a general fashion. I got myself in terrible, very perosnal trouble. Therapy has helped me a lot in my life." She now goes to a woman therapist in Manhattan. It wasn't until Clayburgh's mother was dying several years ago that she began to make friends with her again and today she and her father have become close as well.

She doesn't think, though, that having a neurotic childhood had anything to do with her depth as a actress.

"Since I don't know anyone who didn't have a neurotic childhood I didn't know how to measure that," she laughs.

She began acting seriously at the Charles Street Repertory Theater in Boston after college and at that time thought her future was in the theater. She wasn't pleased with her performances.

"I had one bad part after another, culminating in 'Jumpers.' I didn't know what the hell I was doing. I should have quit. The whole time I was in Washington they were secretly auditioning other actresses, right and left, even my friends, for the part." The final blow was trying out for new-comer David Rabe's play "Boom Boom Boom" and losing the part to Madeline Kahn. So she took off for Hollywood. (She didn't know Rabe at that time.)

That didn't work either. "I was about to give up acting," she says. "I even applied to U.S.C. to get a masters degree in social work. And I would have done it if I had continued getting junky roles. I was too intelligent to get that kind of stuff. I felt humiliated and compromised every day of the week. You feel contempt for the parts, but you're dying to get them. Everyone feels sorry for you because you're doing this - and you feel awfull. Really bad."

Then she got the part of the prostitute in the TV movie "Hustling." "Before I did 'Hustling' I was always cast as a nice wife. I wasn't very good at it," she says. "Then with 'Hustling', it was a nice role and it was a departure. People saw a different dimension."

She says that she has in herself some of any character that she plays. "Even hustling," she says. I didn't know where that came from me for a long time. But it was how I was a teenager - defiant yet vulnerable."

"I'm quite shy," says Clayburgh. "I don't think of myself as a performer. Until I get my character going I'm really quite dull. One thing I didn't like about 'Gable and Lombard' (She played Carole Lombard) was that it seemed to be a little performed. I don't like being knocked out by performances. I don't want anyone to say, 'what a fantastic actor' about me."

It seems a contradiction when Clayburgh says that she's shy. One always wonders how someone could perform very personal things on a screen and still call themselves shy. Especially nude scenes. In "An Unmarried Woman," she has several rather explicit nude scenes but she says they don't bother her.

"They're not ver hard to do," she says. "You always clear the room. Doing it is easy. The hard part is you have to make really thoughtfull decisions about whether it's important to do. I thought in 'An Unmarried Woman' it was important to see her undressing casually in front of her husband and then with somebody else, to show how hard it was for her."

"God," she says with a gasp, rolling her eyes, "compared to some of the things I've seen, that was nothing. I would never want to be seen like Diane Keaton in 'Goodbar'. They had the camera right on her ass. And I would have been embarrassed to do what Jane Fonda did in 'Coming Home.' She had her underpants off and on the screen she was f - and had an orgasm."

She says the big thing now with love scenes is "making them interesting. You have to be thinking hard the whole time."

Everyone always wonders about whether or not people in the movies get turned on when they do love scenes or whether it's just another day on the job. Clayburgh says they do. "Of course you do," she says. "You aren't supposed to not get turned on and you don't necessarily not get turned on again after the scene is over. But you also getangry or hurt when you're doing a scene and you don't stay angry at the person forever afterwards. In movies you get to act out your fantasies. You make a contract with somebody."

David Rabe, she says, "seem not to mind" about her love scenes with other men. "You get pretty immune," she says.

Clayburgh's life with Rabe up until now, though solid emotionally, has been rather scattered physically. The two of them have lived in more than 20 apartments since they've been together, including sublets and rentals in both New York and California, and they were refused one place in New York because Clayburgh was an actress. They got lawyers, tried to sue, then gave up. Now they have a rented apartment in New York, a rented house in California and are thinking of giving up both and going to live in the country outside New York. "I'm getting old and I feel I need a little grass around me," she says.

"It makes me crazed," says Clayburgh. "The truth is I don't like L.A. or California. New York has gotten crowded and dirty and you can never get into a movie anymore without standing in line for hours. In L.A. you have to worry about how you look just to go to the grocery store in case somebody will offer you a part. I don't live that way at all.

"I don't care about money," she says. "I grew up with it. I never spend money on clothes. I haven't spend money on clothes. I haven't bought any new clothes in two years. My biggest extravagance is where to live. Do you know the only magazine I subscribe to is House and Garden."

She leans back against the banquette and sighs. "Where to live," she says, "is the biggest problem I have left in my life. It's neurotic. And David hates all this moving around."

She likes to tell people what an unglamorous life they lead and from the way she tells it, it's true. They rarely go out, she says, and almost never with other copies. When they do have people for dinner, it's usually two, never more than four. They don't hang out with other stars at all. "You wouldn't know the names of any of my close friends," says Clayburgh. And they never get invited anywhere fancy, to any celebrity-filled evening. "I never get on those good lists. I never get invited to screening, either. I've been invited to exactly four screenings in my life. And I refuse to stand in line to see a movie so I usually wait until it gets unpopular and then go. Don't misunderstand. I don't want to go out every night. I wouldn't go everywhere. But it would be nice to be invited, and I would go sometimes."

She beleives basically that being on the circuit, leading the movie-star life is superficial and that's one thing Jill Clayburgh isn't. What really makes her happy is the respect of her peers.

"I really like and care about being respected professionally," she says. "That's it.That's everything. Forget anything else. David is wonderful but I couldn't be happy with him without doing well myself. But David is very, very supportive."

Rabe has recently written a film script with Clayburgh in mind, yet the two of them have never worked together before and she confesses to being apprehensive about it. "One reservation we both have about working together," she says, "is that we're both driven. We each want our own ways. Working separately we both have space of our own. There are certain drives you have professionally which are unbridled. What am I going to sat if he insists on his way? 'You want it that way? Okay?' Never! I'd fight to the last gasp! In real life you can compromise. But professionally . . . it's out of the question."

Jill Clayburgh, at this stage of her life, with her carrer, suddenly has a lot of new fears, new problems she never had before when she was alone, when she was a struggling actress.

"Sometimes," she says, "I'll be frightened that I'll be this really successful actress with no real friends. Lonely at the top. Then there's the 'I'll-never-work-again' fear and the 'I'll-never-do-anything-worthwhile' fear. Plus the fear of hurting myself physically. I'm frightened of my own power and strength.

"I'm only beginning," she says, to be untapped. I should really accomplish something in my lifetime. I'm frightened of it. It's really scary to say what you really want and really feel as a woman. Take the whole Barbra Streisand thing during the making of 'A Star is Born.' (Streisand had a reputation of being difficult on the set.) I don't believe there would have been that scandal if she'd been a man. Her power alone in this industry is amazing. I'd really like to know her. She's the kind of person you'd like to spend a week with. I'm only beginning to sense my own power."

What is most scary to her is how it will affect her relationship with Rabe. "Yeah," she says, "I worry about it. I like to protect the intimacy of our relationship and I also want to be very powerful in my industry. It's tense. It's a strain. The worst part is you feel somewhat that you are operating in a circumference which you have defined yourself."

"If I said, for instance, 'Oh, by the way, David, I'll be directing this or that or acting in this and I'll see you next Christmas' . . . well, I couldn't do it."

She slumps back for a moment, lost in thought, then sits up with what seems a burst of frustrated energy.

"But, boy," she says, "men sure do it."

Then she relaxes back into her seat again and pauses reflectively, before she speaks.

"I guess that's what 'An Unmarried Woman' is all about."