Gillian Freeman, a British writer whose claims to fame included a 1961 novel about a marriage threatened by a homosexual attraction and a fictional diary of a woman in Nazi Germany, died on Feb. 23 in London. She was 89.

Her daughter Harriet Thorpe said the cause was complications of dementia.

Ms. Freeman, who also wrote screenplays and scenarios for ballets including Kenneth MacMillan’s “Mayerling,” published her first novel, “The Liberty Man,” in 1955. Like many of her subsequent books, it dealt with social and sexual distress, in this case a relationship between a middle-class teacher and a sailor of nebulous sexuality.

Homosexuality came into play more directly in “The Leather Boys,” her 1961 story of a heterosexual couple who marry too young and soon find their relationship in jeopardy, in part because the husband develops a close bond with a male biker.