If Joanna Trollope is the queen of the Aga Saga, then Amanda Brookfield must be a strong contender for princess. I don't mean this pejoratively, though the person who first coined the term 'Aga Saga' undoubtedly did.

Both authors specialise in relationships, and characters who live in middle-class, middle English houses centring on the kitchen with its Aga (for those who live on Mars, this is a make of cooking stove). Despite the characters' harrowing experiences, everything usually turns out for the best in the end.

Amanda herself prefers to be described as a modern version of Elizabeth Jane Howard, whose Cazalet saga described the lives and loves of a family in wartime Britain.

Unlike Joanna Trollope, she insists that her books are pure works of imagination and bear no relation to her own life. This certainly seems to be true. While she was the mother of two young children, she wrote The Godmother, about a childless career woman who longs for a baby. Her first book, Alice Alone, written at the age of 29, dealt with a middle-aged woman facing an empty nest.

She started writing novels "to stop myself going mad doing nothing" after her husband was posted to Argentina as a diplomat. They had met as students, in true romantic style, on the playing fields of the Oxford University Parks a venue which features in her latest novel, The Simple Rules of Love.

Now a resident of South London, she has maintained strong links with Oxford, since her son is at St Edward's School and her niece is reading English at Exeter College.

She said: "I would never have put in a character who studied English at University College, like I did. But I thought at 45 I could put an 18-year-old boy at Keble College there is enough distance there and I can describe the setting accurately.

"It's much more fun imagining 'what if' than taking parts of your own life and regurgitating them."

She arrived at Oxford in 1979 as part of the first cohort of girls entering a previously all-male college. "I was in a constant state of terror of being found inadequate, but also one of bliss." As well as singing in the chapel choir, singing and acting in various plays, working and partying hard, she captained the women's university lacrosse team. Her husband, a junior don, played hockey hence the meeting on the playing fields.

She also got a first-class degree, but although she was offered a research post at All Souls, she decided her personality was more suited to the heady world of 1980s advertising.

d=3,3,1Eventually the stressful lifestyle caused her hair to fall out, and she found solace in writing funny stories in her spare time. Meanwhile, her husband had decided to join the Foreign Office after nine years as an Oxford economics don.

His posting to Buenes Aries forced her to turn to writing. With the tension following the Falklands War, spouses were not allowed to work and she started a short story about 51-year-old Alice, which later became her first novel. She secured an agent a few months after mentioning her creative effort to a friend at a dinner party, and her first two novels were well received. However, after starting a family, she hit a creative low for a few years, writing one "bad" novel which remains unpublished.

But for the last 13 years she has produced a stream of novels with gradually increasing sales. Her latest two books feature the Harrison family, which she says is a microcosm for reflecting life's big issues. She created a huge cast of characters, centring on the family home, Ashley House which Amanda says is much grander and larger than her own family home in Sussex, though it played a similar role in family life.

The first Harrison book, Relative Love, ended with Peter, the conscientious eldest son, giving up his right to inherit the house in favour of his carefree brother Charlie. It takes a tragedy to shake the characters up before they eventually pull together and return to their safe world.

Amanda said: "I felt when I finished the first book that I couldn't let the characters go. There was another book there."

But she says The Simple Rules of Love is definitely the end of the saga. "It took two and a half years to write and was very complex. I am trying to write something more simple with fewer characters to juggle. My next book features a 39-year-old divorce who has come out of a very unhappy marriage. It should be the beginning of the rest of her life, but she finds herself looking back instead of forward. She can only get on with her life after she has found out what really happened before."

The Simple Rules of Love is published by Penguin at £6.99.