Her death was confirmed by her daughter Cathy Sylvia, who said Ms. Cassady lapsed into a coma after an emergency appendectomy.

Ms. Cassady, whom Jerry Cimino, director of the Beat Museum in San Francisco, called "the grande dame of the Beat Generation," was a central figure in the real-life circle of friends whose travels across the country in search of kicks and revelation were immortalized in "On the Road." She was the inspiration for the character Camille, the second wife of Dean Moriarty, the "wild yea-saying overburst of American joy" who makes the novel go go go. Dean Moriarty was based on Neal Cassady, her husband during the period recounted in the novel.

For a woman in the 1940s and '50s, this was not an easy role. While her male peers, including her husband, celebrated the freedoms of sex, drugs, literature and the open road, Ms. Cassady was by turns an eager participant and a dissenting adult, the one who kept the utilities on, raised the children and watched with dismay as the next generation of young men emulated the self-destructive impulses of the last.

Her two books, "Heart Beat: My Life With Jack and Neal" (1976), which was made into a 1980 film, and "Off the Road: My Years With Cassady, Kerouac and Ginsberg" (1990), provided a sobering corrective to what she considered misconceptions about the essentially unhappy lives of these men, the poet Allen Ginsberg among them, even while excusing the worst of her husband's transgressions.

"I kept thinking that the imitators never knew and don't know how miserable these men were," she told the novelist Gina Berriault in 1972. "They think they were having marvelous times — joy, joy, joy — and they weren't at all."

Ms. Cassady was born Carolyn Robinson on April 23, 1923, in East Lansing, Mich., the youngest of five siblings in a household that prized Victorian values and books — more than 2,500 of them. Her father was a biochemist and her mother a former English teacher.

The family moved to Nashville when Carolyn was 8. After attending an elite prep school and Bennington College in Vermont, she was studying painting and theater design in a graduate program at the University of Denver in March 1947 when her life took a wild turn — as several lives did in those days — in the person of Neal Cassady.

As Ms. Cassady described their meeting in "Off the Road," she was pretty and demure and owned some jazz records; he was charming and sexually voracious and married. In quick succession Mr. Cassady divorced his first wife, LuAnne Henderson, and married Ms. Robinson. She was pregnant, out of school and beginning the adventure of a lifetime.

Neal Cassady, who died in 1968, was an intoxicating literary protagonist, but as a husband he was a piece of work. Much of their marriage, until their divorce in 1963, involved his running off with other women or with his male friends. During their courtship Ms. Cassady once found him in bed with his first wife and Ginsberg; later, she acceded to his request that she have an affair with Kerouac.

Kerouac portrayed Mr. Cassady as the "holy goof," an instinctual genius who elicited so much of God's love because he gave him so much to forgive. Ms. Cassady was often the first line of forgiveness.

Yet in her writing she stressed his efforts to be a different man: to excel at work on the railroad, to be the paterfamilias for a family that grew to include three children.

"She saw him as the family man trying to provide for the children," Mr. Cimino of the Beat Museum said. "She knew about the guy who had girlfriends, but the way she put it was, 'I married Neal for better or worse, and I was hoping he'd be the man I wanted him to be.' As much as she hated it, that's who she was, the widow of Neal Cassady."

Ms. Sylvia remembered their home as being filled with costumes her mother designed as the artistic director of the drama department at the University of Santa Clara. At other times, the smell of oil paints filled the house from Ms. Cassady's work as a portrait painter.

Ms. Sylvia said her mother was unhappy with the movie made from "Heart Beat," though she liked Sissy Spacek, who played her. Nick Nolte played Neal Cassady, and John Heard played Kerouac. Ms. Cassady never saw the 2012 movie of "On the Road," in which Kirsten Dunst played the character based on her, Ms. Sylvia said.

In recent years Ms. Cassady lived outside London, gardening and painting, often courted by celebrities or fans of the Beat Generation who sought her out. Mr. Cimino said she had slowed down but still enjoyed a cigarette and a glass of wine.

Besides Ms. Sylvia, she is survived by her two other children with Neal Cassady, Jami Ratto and John Allen Cassady; three grandchildren; and six great-grandchildren.

John, who was named for Kerouac, Ginsberg and his father, was with her in England for her final three months and held her hand as she died, Ms. Sylvia said.