But Si's living to regret spilling the beans as both women are raging about his betrayal and are out for revenge.
Dannii feels ‘violated' and Cheryl's told pals she'll never work with the music mogul again.
The breakdown of their friendships follows a week of sensational headlines, sparked by Simon, 52, volunteering explosive details about his personal life in a series of interviews with journalist Tom Bower for unauthorised biography Sweet Revenge: The Intimate Life Of Simon Cowell.
During the chats, he even alleged he had a fling with 'new toy' Dannii when she joined The X Factor in 2007, admitting: 'It was genuine love... It was her hair, the clothes and the tits.'
He also boasted: 'I would've liked an affair with Cheryl,' and branded her a femme fatale, saying: 'I was the mouse with a beautiful cat... She played me.'
Read the full story about Cheryl Cole, Dannii Minogue and Simon Cowell in Now magazine dated 30 April 2012 - out now!
SEE PICTURES Stars arrive at Simon Cowell's 50th birthday party>>
SEE PICTURES The photos of Paul Abdul and Cheryl Cole Simon Cowell didn't want you to see>>
SEE PICTURES Simon Cowell in Celebrity Smokers: VIPs who love a fag>>
SEE PICTURES Dannii Minogue and Kris Smith's relationship in pictures>>
PICS Dannii Minogue and Kris Smith out and about with baby Ethan>>
FASHION GALLERY Dannii Minogue - a style icon>>
MORE PICTURES Dannii Minogue's hair styles>>
