When Sherry Windt looks back on 19 years of growing up there is much that is "hazy, confused" or just plain blank, but of this one point she is certain: "I feel if I had gotten help and my mother had gotten help earlier, this wouldn't have happened."

But it did happen. Windt's mother was stabbed to death in their Bethesda apartment on Oct. 16, 1975. Windt was arrested for the slaying, and last April, after more than two years of legal and psychiatric debate, a juvenile court judge ruled that she was the killer.

Windt, who has spent about a year in jail and several months under evaluation at two mental health facilities, was released June 30 from a Baltimore psychiatric institution after 15 months of intensive treatment there. She still does not remember the night of the killing or the weeks that preceded it. But in an interview, the fragile, dark-haired teen-ager spoke with an air of anguish about dropping out of group therapy a few months before the murder, in June, 1975.

"It's all kind of hazy, but I remember my mother wanted me to work, and she was against it (the therapy)," Windt said as she nervously curled her fingers around a cup of cappuccino at a Baltimore restaurant.

A psychiatrist has testified that she was being treated for a disorder that consisted mainly of difficulty in making the transition from childhood to an adult role. But Windt now says of the treatments, "Nobody thought it was doing me any good. I was getting more depressed. My mother wanted me to work over the summer and therapy interfered."

Windt said she realizes now that it was difficult for her mother "to face that there's something wrong with someone in the family," but she has learned "that it's so important for people to accept having problems and getting help."

Windt has been getting help, treatment valued at nearly $90,000, as a patient at the Institute of Psychiatry and Human Behaviour, a part of the University of Maryland Hospital, in Baltimore. She was sent there by a Montgomery County judge in March 1977, while the courts were still wrestling with the questions of whether she was legally sane when her mother was killed and whether she would be tried as an adult or a juvenile.

The institute treatment, which Windt continues to receive as an outpatient at three weekly lunch-time sessions with her psychiatrist, "is the best thing that's ever happened to me," Windt says. "But I wish it had happened, oh, I don't know, maybe 10 years earlier."

The therapy, she says, has made her "happier, more well-adjusted" than she has ever been in her life.

"But I don't want to think that because I say I'm happier than ever that it means I'm glad my mother is dead because I'm not glad at all about that," she says with fervor. "I'm glad I'm in therapy and I'm getting straightened out, but I'm not glad my mother's dead."

Marjorie Windt, a hard-driving 42-year-old advertising and public relations executive for Garfinckel's department store, was stabbed seven times in the neck and chest in the bedroom of the Bethesda apartment she shared with her only child. About six hours later, Sherry Windt, who had summoned a family friend to the home, saying her mother had committed suicide, was charged with murder.

The charge against the 16-year-old senior at the private Holton-Arms School in Bethesda set off an intense psychiatric debate over her state of mind.

Dr. Reginald Lourie, called by the defense, testified that Sherry Windt was in a trance-like "dissociative state," cut off from reality when the crime occurred and for several periods in the preceeding weeks. Thus, she remembered nothing of what happened.

Psychiatrists called by the prosecution acknowledged that Windt was a deeply troubled young woman, but disagreed with the dissociative state theory. The prosecution agrued that Windt has willed herself to froget the crime.

A juvenile court judge ultimately ruled that she was legally sane at the time of the killing and that she was reponsible for her mother's death. But because the focus of juvenile court is rehabilitation rather than punishment, he ordered further psychiatric treatment and approved a treatment plan. That was last April 25.

On June 30, Windt left the institute, to live with a nurse who had befriended her there and work full-time in a store not far from the grounds.

Windt is supporting herself with the job, according to her attorney, Walter Madden, and, according to an uncle is "living as modestly as she can." Marjorie Windt, the uncle said, left no estate.

Windt says she is able to discuss her feelings about her mother, "but I don't want to now. Certain things are private and I don't think it would be appropriate," she added, her eyes suddenly downcast.

Her mood changes are swift, announced with a girlish giggle when she discusses her newfound freedom or a sudden downward glance when a question is too sensitive. She says she hates publicity and hopes this is the last time she will have to see her name in a newspaper.

At 19, there is a worldly sophistication about her that comes out in her flawless order in French from an elegant restaurant menu, her comments on the food and her request for cappuccino at the end of the meal.

But with her long, dark hair pulled back in a neat braid for the hot summer months and her face devoid of makeup, she looks more a teen-ager than she did during her court appearances.

There is a boyfriend in her life today too, 25-year-old Erik Marks, who accompanied her during the interview for moral support. The two met at the opera, while Windt was on a special outing from the institute, according to a cousin.

Windt says her greatest desire now is "to make a normal life."

She is looking forward to college this fall and hopes to get a scholarship. She doesn't know precisely what she wants to study - "I don't want to limit myself" - but she is sure to what she does not want to be - "a nurse, a psychiatrist or a psychologist."

She won't say where she is planning to go to school because she doesn't want her past to follow her there.

"I know it's impossible for me to forget about everything . . . impossible to forget what's happened, being arrested and what led up to it and everything since. It's impossible to forget, but the biggest thing is to learn from what happened and to deal with things more constructively."