She had herself broken off her relationship with the millionaire playboy, she said - but was keeping a ring he gave her "as security".
Today and all this week you may read Ms Fisher's tear-stained tale of Mr Fayed's alleged perfidy in the tabloids, she having sold her story for a tidy sum.
Yet Suzanne Gregard, Mr Fayed's ex-wife, yesterday told the Independent on Sunday that she had met Ms Fisher while dining on Los Angeles' Sunset Boulevard with mutual friends a fortnight before the launch of Ms Fisher's scorned-woman lawsuit against Mr Fayed, and heard a rather different version of events.
"A couple of weeks ago I was in the Sky Bar on Sunset Boulevard with friends when we ran into Kelly Fisher, the ex-fiancee," said Ms Gregard. "She said: 'I broke up with him. I've had enough.' But she also said: 'I've kept the ring - I'm no idiot'.
"The next thing I know is she's on the news crying hysterically and flashing the ring and saying she's suing Dodi. I thought it very curious."
On Thursday evening Ms Fisher began proceedings against the 41-year-old son of the Harrods owner, Mohamed Al Fayed, claiming damages for breach of contract and "distress" following the publication of photographs of Mr Fayed junior apparently kissing the Princess of Wales aboard his luxury yacht. By Friday, a deal believed to be worth at least pounds 200,000 had been reached between Ms Fisher and Rupert Murdoch's newspaper group News International for her story, to be run in today's News of The World, followed by a five- day serialisation in the Sun newspaper. But Mr Fayed is a man of the world. He knows, in such circumstances, to whom one turns. One fights fire with fire. Enter Max Clifford, supreme purveyor of tabloid "kiss 'n' tells", who has now been retained to advise Mr Fayed on how best to present his side of the story.
In a counter-blast to his client's ex-lover, Mr Clifford said there never had been an engagement. If there had been, Ms Fisher would have been the first to announce it. All the world's gossip columns would have featured the engagement, but there was not even the slightest mention. So there. As for the ring, uncannily similar to the engagement band Prince Charles once gave to Diana, produced by Ms Fisher for the world's press, Mr Clifford said there was nothing significant about it. Mr Fayed, said the publicist, "has given loads of rings, watches and jewellery to women in the past".
Ms Fisher and Mr Fayed, the publicist said, split up because they both felt the relationship was going nowhere. A friend of the Harrods owner, Mr Clifford was drafted in to deal with the tabloids.
Since by extension, he can be said to be advising Mr Fayed's present lover, the Princess of Wales, it marks the first occasion that the kiss 'n' tell king has represented royalty, surely some sort of milestone in the increasingly curious progress of the House of Windsor.
Curious too is the matter of Mr Fayed's allegedly illustrious film career. He has always been credited with having been associate producer of the Oscar-winning Chariots of Fire, with having had the vision to put his own money behind the movie. However, executives involved in the making of the film say the money, $3m, came from his father and Mr Fayed's role was virtually non-existent. Mr Al Fayed paid the cash through Mr Fayed's company, Allied Stars, which is how he got the credit.
The image of him as a major player in the film world was met with a cough, one might say. "He has no real presence of any kind in the movie business," said one well-known producer. Hollywood, he said, was full of Dodis.
Ms Fisher's lawyer, Gloria Allred, alleges Mr Fayed had bought her new client an engagement ring in Paris - and then ended the relationship to pursue a romance with Diana.
Ms Gregard, who has since re-married, said she had spoken to Mr Fayed once since the enthralling story of Di and Dodi began "because I was being bombarded by the press and I wanted to know what I should do". Mr Fayed had confirmed to her that "he was seeing Diana".
Ms Gregard felt unable to suppress just the tiniest bout of mirth when she heard that Mr Fayed and the Princess had been to consult a psychic. "Dodi and I went to see an astrologer before we got married," she said. She said the astrologer had not revealed just how brief their marriage would be.
Meanwhile, the Princess herself this weekend is taking a break from the attentions of the British media - by going on holiday with Rosa Monckton, wife of Dominic Lawson, editor of the Sunday Telegraph.
The Princess and Ms Monckton, who is also President of Tiffany & Co, the jewellers, flew to the Greek islands for Diana's third Mediterranean cruise in a month - in a Harrods jet.
August - Diana's very own month: five tabloid years of tears, treachery and titillation
Diana, enraged by pictures of Charles playing with the children, took a trip to Disneyworld - accompanied by the press - to remind the public which parent gives the kids a good time.
Accusations that she plagued art dealer Oliver Hoare with nuisance calls. She claimsPalace insiders framed her. Her former lover James Hewitt claims that he, too, received anonymous calls.
Hopes of a scandal-free summer died when a Sunday tabloid exposed Diana's friendship with the England rugby captain, Will Carling. Denials and threats of legal action ensued, but the story was given a boost when Carling's wife, Julia, attacked her rival's allegedly flirtatious
behaviour. Julia Carling's comments precipitated what the press successfully built into a fashion war between the two women.
The Royal Divorce was finalised on 28 August, ending a month in which Diana obtained an injunction against a photographer whom she accused of stalking her. Paparazzi followed Diana to her first public engagement after the divorce. She appeared still wearing her wedding ring - to confirm her famous threat: "I'll not go quietly." And she hasn't.
August 1997: That kiss.Reuse content