In both her professional and personal life, Marilyn Monroe often spoke of her wish to to beyond her image as the sensuous temptress ever available for casual lust. In a dumb-blond role in "Bus Stop," she confides to a traveling companion that, "The man I marry has to have a real regard for me, besides all that loving stuff."

To Hans Jorgen Lembourn, a Danish writer who kept a diary of the 40 days and nights he and Monroe passed through each other's lives, she said, "What's important is that I love (someone), not that I'm loved."

Lembourn's account of how Monroe struggled to shake loose from the torments of her life for a few days of a loving relationship with him is worth-while reading. Despite the tease of the title, it is tastefully written. And despite the success Lembourn had in capturing Monroe's heart, it underscores the timeless truth that a successful union between a man and woman has to do with much more than heart-felt fellings.

A number of books about Monroe have been written since the former Norma Jean Mortensen died 17 years ago. Some have offered "the untold story," while others, like Norman Mailer's, were projections of the author's fantasies. Lembourn, with no pretensions and only occasional lapses into the rhapsocid - Marilyn was "the mythical Earth Mother, and anything mankind knew could flow from her" - tells a story of instability and how he and Monroe tried for a moment ot temper it with emotional love.

Monroe deserves the attention of another book. In the annals of 20th-century hedonism, she became one of the world's most noticed and exploited pleasure symbols. Hollywood had created love goddesses before, but Monroe was the first to turn sexiness into a cash crop of bumper proportions. The take, whether figured by the ensuing financial success of Playboy, Penthouse or the other gynecological magazines, or the jiggly shows now on television, has been mammoth ever since.

In her personal life, Monroe had the substance to win as husbands Arthur Miller, the cerebral playwright, and Joe Dimaggio, a sports hero. She was associated with President John Kennedy.

As the lover of Hans Lembourn, she had all she could do to break free of what the Dane called the "honor guard of rescuers around Marilyn." She liked Lembourn because he allowed her to love him without too much meaning being dumped on the relationship.

By the time they met, she already was overloaded with so many tragedies that even taking on the pleasant responsibilities or romantic love was almost too much. Her mother was a schizophrenic. Her father vanished after the child's birth. She was raped at 9. She had a speech problem. She couldn't hear in one ear. She as half-addicted to alcohol and fully addicted to pills that either eased depression or induced sleep.

"When I was young," she tells Lembourn, "I didn't drink and didn't take pills; I was happier, I slept, I believed what people told me. Now I drink and stuff myself with pills, and the whole thing only gets worse, and I think more and more often of my mother and what happened to her . . . Could I have an insanity in me that grows with age?"

Lambourn answered that he thought not. He found in her many of the same neurotic needs and displays of self-absorption that others had discovered. But whatever the flaws and pains, Lembourn describes a woman who saved herself from destruction - at least for a time - by her large capacity for honesty about herself. She was the celebrated actress who wouldn't buy her own act.

As a lover, Lembourn was the rare one who knew the art of attentiveness. He was able to pay attention fully - as do all skilled lovers, whether in a doomed adulterous fling or a 50-year marriage. People fall in love for numberless reasons, but basic to them all is the desire to get another person's full intellectual and emotional attention. Loving the other person hen becomes natural.

Lembourn describes a trip they took - a week of driving in a white Buick convertible from New York City to Memphis for a ride on the Delta Queen to Natchez. From begining to end, he cares about nothing except Marilyn. She tells him that "I fall in love easily, and I like it, and I also like to go to bed with them, but then I discover that they're not interested in me at all but in themselves; they're after something, or they think it's enough to be good-looking. The hell with their good looks . . . I want men who are courageous, honest and talented, and wear glasses and have crooked teeth if it so happens. I'd rather do without men than be together with men I'm lonely with."

From Mississippi, the couple flew to Los Angeles where Monroe returned to her studio for her next film. Lembourn returned to New York. They never met again.

His diary is a poignant and necessarily dispiriting piece of writing. Marilyn Monroe helped shape part of two country's culture as we know it - and endure it - today. What shaped Monroe is worth knowing about.