Sylvia Plath film has lost the plot, says her closest friend

Forty years after Sylvia Plath gassed herself in a flat in London at the age of 30, the American poet's uncanny ability to provoke the extremes of emotion is undiminished. Sylvia, a new film of her life starring Gwyneth Paltrow, has been condemned by her closest friend as a misleading, over-miserable "myth".

Elizabeth Sigmund - to whom Plath's best-known work, The Bell Jar, is dedicated - was close to both Plath and her husband, Ted Hughes, whom she married in 1956. Ms Sigmund lived near Plath and Hughes - who later went on to become Poet Laureate until his death in 1998 - in Devon.

Ms Sigmund was an early script adviser on the film, although Plath's family refused to have anything to do with it, angry at the "industry" that has grown around her death. She is one of few people alive who witnessed at close hand the twists and turns of Plath's journey towards suicide after seven years of marriage to Hughes, which ended with her death in February 1963 when she put her head in a gas oven. Earlier this year, Plath and Hughes's daughter, Frieda, expressed her disgust with the Plath "industry", and the film, by writing a poem - "My Mother" - in which she spits at the "Sylvia Suicide Doll" culture.

Now Ms Sigmund has also attacked the film - which goes on general release next month - for portraying her friend in an unrealistic, mythical, clichéd and simplistic way. She also claims a key turning point in the film was made up.

Speaking last night to The Independent on Sunday, Ms Sigmund, 75, told of her anger at seeing the finished film, which was part-produced by the BBC and the British Film Council. It has, she says, lost much of the truth conveyed in early versions of the script, which she had approved.

"There were a number of things which the writer just didn't take on board," she said, "which was how happy Ted and Sylvia were... and that they'd had a huge circle of friends. This was all left out. When I actually saw the film, I was very disappointed.

"In this film, [Sylvia] was portrayed as a constant depressive. The film is unremittingly dark... When they lived in Devon, there was so much laughter and fun," explained Ms Sigmund, for decades a campaigner against chemical weapons. "Ted used to come over and visit us, and he used to sing folk songs with us, but she was very humorous. No one ever thinks of her being fun - but she was."

Ms Sigmund is especially angry about one central episode in the film. In it, Plath is portrayed as raging over the arrival at her house of Assia Wevill, with whom Hughes was having an affair, and her husband. She throws them out. Plath then is seen driving to the sea, and staring out bleakly over the ocean.

"The scene never happened," says Ms Sigmund. "It very much annoys me. It makes Sylvia look very ill-mannered, very aggressive and very suspicious. She never treated them like that. She certainly would never have had a row over the food or turf them out... It doesn't show that she had friends who loved her."

Ms Sigmund's first-hand recollection of that day is very different. "She actually put Nick [Plath's son] in the car, drove straight up to us and stayed the night. The next morning we found her kneeling over a box that held an old cat and her kittens. And she said: 'Aren't they amazing, they're so absolutely new.' So even then, despite her misery, she was still interested in other living things... These myths about her being only interested in herself are completely wrong."

However, Ms Sigmund does recommend that people should see the film - especially women artists. "For a woman to be driven as she was by an incredible talent, while striving to be a perfect mother, a perfect wife and a perfect poet - she was struggling with all of these things. And then to see the mainstay of your life, which Ted was, just going - everything just collapsed for her."

Ms Sigmund singles out one part of the film that is true to the real Sylvia. "There's a lovely scene of her and Ted in a punt on the River Cam, with her reciting Chaucer to cows on the river bank as she stood up in the punt - this is one of the few scenes in the film that reflects her humour and wit.

"The film enhances the idea that Sylvia was a permanent depressive and a possessive person - which just isn't true.

"The film has an atmosphere towards the end of her life which is heartbreaking in its accuracy," Ms Sigmund concedes.

Last night makers of the film defended it as "honest". "This is a responsible film," said Charles McDonald, the film's publicist. "As with any dramatic version of anyone's life, some dramatic licence is inevitable. John Brownlow, the scriptwriter, went into this with a great sense of responsibility. It's as balanced a view [of Plath's life] as there has been yet. John did research the story very thoroughly, and was at great pains to make the story as factual as possible. We respect Elizabeth's views. John's is an emotional interpretation of Plath's life."

The real reaction of Hughes - played in Sylvia by Daniel Craig - to Plath's death was, says Ms Sigmund, immediate and unambiguous. "Ted was absolutely devastated," she says. "I think he was caught up in something he couldn't cope with. I think he was heartbroken, and he remained heartbroken. He handed me a copy of The Bell Jar.

"I knew she was going down in a cycle of depression, but she had been given anti-depressants. I think she committed suicide because of a combination of factors, and a feeling that she was an alien in an alien land."