Thanks for all the comments, even some of the ones that are a bit nasty looking, they\re all helpful in a way to understand common thinking about these things. I'm sorry for keeping coming back to MN, but I literally have no one I can tell or talk to about it so I am probably just venting or thinking out loud on here.
I just wonder will I ever get over the shock of it all, I feel in shock pretty much all of the time. The circumstances (which I'm just too embarrassed to share right now), I just find really shocking, particularly two of them. Quite aside from being unfaithful I just never imagined she had it in her.
To all appearances she's a middle class, well brought up, stable, educated professional, sociable, polite, likeable normal person. Kind, interesting, empathetic, compassionate, a terrific parent etc. I do still really love her for all of that among other attributes. But the circumstances of her infidelity are like complete Jekyll and Hyde. Seedy, devious, extreme, dangerous.
I now think the person I thought I knew all these years, I just don't know her.
I think back to good times in our relationship, shared experiences etc, but now they're all at least tinged, if not ruined by thinking what was she really up to, concealing or even just thinking about without revealing.
Yes there's a big part of me just wants to leave and break all ties, but I'm not convinced it'll stop me thinking about it obsessively like I am. And, at the moment at least, I just can't get my head around the practicalities. Added to that our eldest will be going into GCSE year and I can't imagine the effect on them.
For now, how do I cope with the shock?