BOOKS / Daphne's dilemma: Daphne du Maurier had affairs with women, but she despised lesbians. Being a writer was a way of being the man she wanted to be, as a new biography reveals

Daphne du Maurier was born in 1907, the middle of three daughters of the actor- manager Gerald du Maurier. They were an affluent, unstuffy, slightly bohemian family, keen on holidays and socialising, with their own Mitfordian private language - 'wain' for embarrassing, 'honky' for vulgar, 'wax' for making love, and so on - though when there were no visitors to perform for Gerald would sink into depression. He was lavishly unfaithful, as even the children knew, and Daphne was puzzled by her mother's apparent indifference. She was a cold mother, and Daphne later told a friend: 'I can't remember once being held by her, feeling her arms round me, sitting on her lap. All I can remember . . . is someone who looked at me with a sort of disapproving irritation, a queer unexplained hostility.'

Daphne, like her sisters, was patchily educated by governesses: she was not required to do anything more than make a good marriage. But some time in her late teens she developed the burning ambition to be a writer, and stuck with it despite all her family's attempts to distract her. This may have been connected with the discovery of Cornwall: her parents bought a holiday home in Fowey when she was a teenager and she often stayed there alone. It may also have been connected with her first lesbian affair, with her French teacher, when she was 18, because writing was somehow connected with masculinity in her mind.

She was not wholly or even primarily a lesbian; after this first teenage pash, she fell in love with the film director Carol Reed and then with 'Boy' Browning, an Army major and Royal courtier, whom she married. The marriage was happy for several years and produced three children. But when Browning came back from the war, he showed no inclination to resume sexual relations (though Daphne was still a beauty in her late thirties) and, bewildered and depressed, she turned to women for comfort, pursuing first Ellen Doubleday, her publisher's wife, who did not reciprocate, and then Gertrude Lawrence, who did.

But her strongest, most lasting love affair was with Menabilly, the hidden Cornish house that was the model for Manderley. She first saw it, empty and almost derelict, in 1926 and finally got a lease and moved in during 1943. It was cold, uncomfortable, infested with rats and partly falling down, but as she told a friend: 'It makes me a little ashamed to admit it, but I do believe I love Mena more than people.' And when she finally had to move out, in 1969, she wrote: 'Houses are not like marriages . . . one cannot just walk out and leave them.' In fact, she did not walk out on her marriage either, but stuck with Boy to the bitter end. Bitter it was, though: she admitted to her friends that she found her husband 'pathetic'.

Her attitude to being a woman was hopelessly confused. As a child, she didn't just long to be a boy; she thought she was a boy who had somehow got into the wrong body. It was this boy who was the writer: hence perhaps the often harsh treatment of women in her novels. Throughout her life, she liked to wear masculine clothes and dressed her own daughters as boys when they were little. Although she told her old governess that 'I like women much better than men', she was no feminist, and believed women were the inferior sex. Before the birth of her first child, she had the nursery painted blue, with the name Christian on all the doors; when a prospective nanny pointed out this could be awkward if the baby were a girl, she muttered fervently: 'Heaven forbid]'

Despite her unconcealed disappointment at having two girls before the longed-for son, she proved a good mother in the end and remained on affectionate terms with all her children. She had gone into marriage expecting to have to be the main breadwinner - as indeed she was - but she always felt that her success had damaged her husband. She wrote to Ellen Doubleday: 'It's people like me who have careers who really have bitched up the old relationship between men and women. Women ought to be soft and gentle and dependent. Disembodied spirits like myself are all wrong.' However, she never for a moment considered giving up writing. Most confusingly of all, she always expressed great contempt for lesbians, even when she was writing yearning love-letters to Ellen Doubleday and having a physical affair with Gertrude Lawrence: 'By God and by Christ if anyone should call that sort of love by that unattractive word that begins with 'L', I'd tear their guts out.' I wonder whether she would have been an even better writer if she had been born a couple of generations later, when feminism and psychoanalysis might have helped her articulate her confusions? Or was it precisely because she was so bottled-up that she achieved such intensity in her work? It is still hard to know how good a writer she was, perhaps because she fails to fit conveniently into any Eng Lit niche. She violently objected to being called a romantic novelist and, if she had to be categorised, preferred the 'macabre' slot. Certainly she was not a romantic novelist in the girlish pillow-fantasy sense. But Margaret Forster is right when she says that she is Romantic as the Brontes are Romantic. She had no truck with realism or contemporary life: when she was only 13, she wrote to her governess: 'I have become an idealist, realism is so earthy and sometimes sordid - very often in fact.'

Apart from two short stories, 'The Birds' and 'Don't Look Now', all her important works are set in the past. Another problem is that while her best novels - Rebecca and The Scapegoat - are outstanding, many of the others are pretty dire, including, I would say, those two hardy perennials, Jamaica Inn and Frenchman's Creek. She was hopeless at dialogue and sometimes shaky on characterisation; her forte was atmosphere, the sense of place and narrative drive. As Gollancz's reader, Norman Collins, commented when he first read the manuscript of Rebecca: 'I don't know another author who imagines so hard all the time.'

Interestingly, when she first showed her teenage short stories to her father, whom she adored, he said that she might one day be as good a novelist as his father, George, whom he adored. And Rebecca is oddly like George du Maurier's Trilby, in that it is a perfect book that doesn't seem to lead anywhere. Did her father unwittingly limit her by that remark? Suppose he had said she might one day be as good a novelist as George Eliot, could she have aimed higher, achieved more?

Margaret Forster makes du Maurier far more sympathetic than I would have expected. I thought at first that Forster's North-country plain-spokenness might make her impatient with some of du Maurier's upper-class affectations, but in fact she handles these, as everything else, with generous good humour. The biography is briskly written, just the right length and convincing throughout. I wouldn't have minded just a bit more discussion of the novels, but Forster was obviously keen to keep the narrative rolling.

Daphne du Maurier was praised for making her biography of her father, Gerald: A Portrait, read like a novel, and I am tempted to say the same of this biography, though, from one who much prefers reading biographies to novels, it might sound like a double-edged compliment. In any case, what does it mean? Perhaps that it is a little bit too digested; that Margaret Forster's interpretation of her subject is so complete and so persuasive that it leaves nothing for the reader to do except admire and enjoy.

'Daphne du Maurier' by Margaret Forster is published tomorrow by Chatto at pounds 17.99