Dear Coleen

I’m a 28-year-old man and need advice after sleeping with my best mate’s ­girlfriend.

It was a one-off and we both regretted it afterwards, even though it was great fun at the time.

It wasn’t planned – she asked me if I’d come over and check her car, as she thought she had a flat tyre and her boyfriend was away on a stag weekend.

I stayed for some food, we had a few drinks and when I went to leave she kissed me goodbye at the door.

One thing led to another and we ended up in bed, and I stayed the night.

The next morning, we talked about it and decided we wouldn’t do it again.

It’s a difficult situation, though, because I see her boyfriend a lot – he’s been my best mate for years and we also meet as a group with our girlfriends, who also get on really well.

I don’t want our friendships to change – is that possible?

I’m terrified we’ll trip up and give the game away when we are all out together, and the guilt has been driving me mad.

I’ve learned my lesson big time, but I don’t want to fall out with my mate. What should I do about it?

Coleen says

If you don’t tell him or he doesn’t find out, you’ll still both know what you did, so I think it’s going to affect the group dynamic anyway.

If you decide not to come clean, then I think it’s really important you’re on same page with his girlfriend – that it will never happen again and you’re never going to tell your partners or anyone else.

The problem with this is, I don’t think you can ever be really sure he won’t find out – what if his girlfriend blurts it out in anger the next time they have a row?

He might not find out for five years or maybe never, but it could be next week! That’s the chance you take.

You’ll also have to embrace the guilt, so it’s whether you can live with that.

I think you probably know that if he finds out you will no longer be friends.

He might carry on with her, but I think you’ll definitely be out of the picture.

I just wonder why you did it? When I was with my first hubby, I had one of his mates living with me for two years and it never came to that, however drunk we got and however many deep conversations we had.

That line was never crossed, not even in my thoughts. So, I think you have to work out why it happened (and don’t blame the booze).

Has there always been something between you?

I kind of hope that is the case or you’ve risked an important friendship for a night of meaningless sex.

Also, perhaps give some thought to your own girlfriend and what this means for your relationship.

As far as I can see, you seem to be more concerned about your mate.