'If you look at the studies into paternity, even conservative figures show that between eight and 15 per cent of children haven't been fathered by the man who thinks he's the biological parent.' That's a lot of women keeping a lot of secrets.
One woman I know - let's call her Juliet - has been married to Adrian for ten years, and having an affair with Mark for the past two.
Female infidelity tube chat
The news that Farrah Fawcett had a secret affair for 11 years without telling a soul is a classic example of the way a woman cheats: discreetly, in secret, and while carrying on with the rest of her life as normal.
It has been met with hot denials by Ryan O'Neal, but - and I'm sorry to break it to you this way, Ryan - you'd be the last to know.
However, despite her best efforts the husband could not be persuaded to cheat.
He held his ring up to the model and said: 'I'm married.' Kristina ran after the man and squeezed his bottom causing him to shout: 'F*** you little girl!
Instead of marriage counseling, self help, or simply talking marriage problems out, men and women are relieving their stress online.
Here I give you a list of ten online “cheater” websites.
‘I couldn’t sleep or eat and felt sick most of the time at the thought of what he had done,’ says Kelly.
Her sole focus became the welfare of their two daughters, Megan, nine, and Madison, four.
She has told me and her sister - otherwise, she says, she's '100 per cent certain' that nobody else knows.'I won't allow Mark to call me on my mobile or email me, ever. I insist we talk on our office landlines, and when we meet for drinks or dinner, we pay with cash.