"The idea of someone who's continuously being pushed to the edge is what fascinates me," she once said.
Her play "Shay," presented in 1983 at the Coronet Theatre in Los Angeles, featured an acutely shy woman who purposely slashes her mouth after an agonizing social occasion. But she also admires snow because it makes everything match.
Commire, who was also an editor and author, died of cancer Feb. 23 at her home in Waterford, Conn., said her friend, actress Mariette Hartley. She was 72.
One of Commire's more controversial works was "Put Them All Together," which premiered in 1982 in Los Angeles at the Coronet. It starred Hartley as Maggie, a woman who falls apart mentally while trying to cope with her destructive, hyperactive young son.
The "absorbing," powerful play tackled an "unmentionable" subject rarely dealt with in the theater, a mother who kills her child, theater critic Dan Sullivan wrote in 1982 in The Times.
Another critic had labeled the play "anti-child and anti-motherhood," Commire lamented in the article. But its message was "just the opposite," a cry for help, she said.
"She wrote a great line when her best friend comes to the house and Maggie says, 'Oh god, talk to me in adult,' " said Hartley, who considered Commire her best friend. "That's what she did for me in life — she talked to me in adult."
Born Aug. 11, 1939, in Wyandotte, Mich., Commire earned a bachelor's degree in 1961 from Eastern Michigan University.
She started out as a teacher but was soon writing the first of several plays. Four times between 1973 and 1988 Commire received the Eugene O'Neill Theater Award, and her plays were staged around the country and in Britain.
"Shay" was based on her mother, and "The Melody Sisters," a play about singing siblings who reunite in middle age, was about her aunts. Her final play, "Starting Monday," addressed the deep friendship of two women; Commire said she wrote it as a catharsis after a close friend died of cancer.
Commire co-wrote "Breaking the Silence," Hartley's 1990 autobiographical account of a troubled early life. "We just thought alike," Hartley said of their book-writing partnership.
As the editor of "Women in World History: A Biographical Encyclopedia," Commire researched the exhaustive 17-volume compendium for more than a decade. It received the Dartmouth medal for outstanding reference work in 2002.
She had edited reference books for Michigan-based Gale Group since 1973.
Just before she died, Commire completed her final project, "Mooreville," a book about her family's struggles during the Prohibition era.
She is survived by her brother, Ron Shedd, and stepsister, Judy Trupiano.