The former X Factor judge has told The Mirror that she is unhappy about getting a mention in Tom Bower's unauthorised tell-all, Sweet Revenge: The Intimate Life of Simon Cowell.
Sharon told the paper: "I'm not Simon's mother - I don't give a toss who he f****. That's none of my business. I think Simon thought he'd have complete control over this book.
"But how dare he bring me into it now? I don't want to be dragged into his little world of debauchery, thank you very much."
But Mrs O, who told The Mirror that she was approached by Bower but refused to contribute, said: "Dannii wanted to be mistress of Simon Cowell - and the mistress of X Factor.
"But I didn't leave the show because Simon and Dannii were f******, I left because she became unbearable."
Yesterday, publicist Max Clifford confirmed that Simon "did have a relationship with Dannii".
However, he criticised Cowell's decision to discuss details of his private life, telling Exclusive TV: "It was Simon's choice, but my attitude is you don't talk to someone like Tom Bower, he's only really looking for the controversial stuff. It was a mistake."
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