As divorce cases go, it is as explosive and sordid as it gets: a woman catches her husband having sex with a prostitute, forgives him, but finally throws in the towel after discovering he has been unfaithful again. Yet absolutely none of it happened in real life.

Amy Taylor is divorcing David Pollard, her husband of three years, on the grounds of "unreasonable behaviour" after she discovered his character in the online community game Second Life had been having an affair.

It was the second time that Ms Taylor, 28, had caught her husband's virtual alter ego being unfaithful. Before they were married, she had once awoken from an afternoon nap to discover him sitting at his computer watching his online character – whom he had named Dave Barmy – having sex with an on-screen call girl.

She said: "I went mad – I was so hurt. I just couldn't believe what he'd done. I looked at the computer screen and could see his character having sex with a female character. It's cheating as far as I'm concerned."

Ms Taylor later forgave him, and the couple, who met in an internet chatroom in 2003, married at a register office in Cornwall in 2005. Dave Barmy and Amy's avatar, Laura Skye, held a lavish ceremony in the virtual world to mark the occasion. But in April this year, she caught his character in flagrante for a second time. "I caught him cuddling a woman on a sofa in the game. It looked really affectionate," she said. "He turned off the computer monitor, and I turned it back on and demanded to look at his chat history.

"But he turned off the computer so the history was all deleted – and I ended up going off to his mum and dad's in floods of tears. He never did anything in real life, but I had my suspicions about what he was doing in Second Life."

The day after discovering his online affair, Ms Taylor filed for divorce, which is set to be finalised next week. Their virtual divorce went through in the Second Life courts in May. She is so furious that she has already reverted to her maiden name by deed poll.

Mr Pollard, 40, admitted he had been having an online affair with a woman from America, and the pair's characters are now engaged in Second Life. But he insisted that his real marriage had been a "bit of a joke", and that his affair was prompted by his wife's addiction to the popular fantasy role-playing game World of Warcraft. He said: "I was having this online relationship with this girl in America. It was nothing really major, but then Amy found out about it and went mad, and said 'how could you do this, you bastard?'

"Amy never did anything around the house. She just played World of Warcraft all the time. If I wanted to spend time with her I had to ask, but it was always too much trouble for her to come off the game to spend time with me, so the marriage was a bit of a joke."

Ms Taylor's love life has since moved on, but she does not seem to have learnt her lesson. She met her current boyfriend while playing World of Warcraft.