'He told me he'd been sleeping with my wife and they were going to set up home together. It felt like a double betrayal: my best friend sleeping with my wife.
'I wanted to hit him, but I knew an angry scene would only leave me feeling worse.
Chris happily went along with it, even caring for the children when his wife went away on business trips with his friend.
'I suppose the relationship took off during one of those trips,' he says.
'Crushed' and 'powerless' are the words he uses to describe his feelings after discovering his wife of 11 years had betrayed him.
'Lucy and I were going through a difficult time,' he says.
I wanted to act as a gentleman and not as a hard man.' Chris didn't return home for three days.
'He said he wanted me out of the house and said that he couldn't forgive me.' It is, undoubtedly, a sorry tale, but Ruth's story is far from unique.For a betrayed man, it's an offence against his manhood.It goes right to the core of his identity.' This was the experience of designer Chris Davies, 47, who divorced his wife, Lucy, after she started a relationship with his best friend.And as an accredited coach and counsellor specialising in women over 50, I have noticed the increasing frequency of female infidelity.It seems to me that while once women would have felt obliged to stick at an ailing marriage, these days they don't feel so compelled to stay.