Josephine Hart, who has died aged 69, wrote short, spare novels about tangled love lives, and forged a successful career with bestselling books such as Damage (1991) and Sin (1992).
As the wife of Lord (Maurice) Saatchi, legendary co-founder with his brother Charles of the advertising agency Saatchi & Saatchi, she was at the heart of Britain's cultural elite; but her childhood in rural Ireland was blighted by profound personal grief.
At the age of six she lost her brother Charles, followed some years later by her younger sister, Sheila, who had been brain-damaged as a result of meningitis and paralysed from the age of two. Within a year, another brother, Owen, was killed in an accident. Josephine was then 17, and in her last year at school, preparing for exams.
After school she remained at home for four years, reading voraciously. The pain caused by the deaths of her siblings led her to withdraw from the world: "Deep down, I made a bargain with life: I'd behave honourably, but would not make a more serious contribution or do anything creative."
Only many years later, in the mid-1980s, encouraged by her second husband Maurice Saatchi, did she overcome this feeling. Locked in her study, she wrote by hand the first chapter of her first novel Damage in the course of a single morning.
The book, which she finished in six weeks, concerns a middle-aged government minister who develops an erotic obsession with his son's girlfriend. Hailed by Ted Hughes as "really a poem", and by The Washington Post as "a masterpiece", it was translated into nearly 30 languages and sold more than a million copies worldwide; in 1992 it was made into a film directed by Louis Malle and starring Jeremy Irons and Juliette Binoche.
Josephine Hart was born on March 1, 1942 at Mullingar, Co Westmeath. By the age of 12 she could recite Shakespeare sonnets, poems by Yeats, Eliot and Auden, and lines by Gerard Manley Hopkins.
In 1964 she left Mullingar for London, where she worked in the telesales department of a newspaper while taking acting classes at night.
She moved to Haymarket Publishing, became the firm's only woman director and launched several trade magazines; it was there that she met Maurice Saatchi, and was briefly his boss.
She produced several successful West End plays and presented a series about books for Thames Television before, at the age of 44, writing Damage. Her second novel Sin is about a woman who seduces her adopted sister's husband and moves in with him.
Her regular poetry evenings at the British Library were renowned for their stellar casts -- she charmed Roger Moore into reading Kipling and Ralph Fiennes into reading Auden.
In her last novel, The Truth About Love (2009), a study of family grief, Josephine Hart drew on her own childhood in Ireland -- it begins with the dying agonies of a boy fatally injured in an explosion.
Josephine Hart's first marriage, to the publisher Paul Buckley, was dissolved. She married Maurice Saatchi in 1984; he survives her with their son and a son of her first marriage.