My only qualification on this subject comes from the fact that I have been where you are now. Mumsnet proved to be a lifeline to me and hopefully it will be for you too.
How did you find out about the affair - did he confess without any outside influence? Or did he get caught? That is quite important.
What is he proposing to do now? Is he offering to make changes by moving jobs. Is he offering to go to counselling?
These things will give you an indication about how serious he is about never going there again. Only you can decide whether you can forgive him and trust him again. Counselling would help with that, as would Not Just Friends by Shirley Glass. It was recommended to me on here and DH and I have both read it, it is very helpful.
We are a few months down the road and though it was horrendous at the time, and I still get down-days I think in a bizarre way it kind of saved our relationship. We were sleepwalking towards separation and the shock of his affair woke us up to what we may be losing. Obviously he has had to do most of the changing but we are both in a better place.
What helped me to recover our relationship was the fact that other than one very good friend and our counsellor (and on here
) I have not discussed this with anyone. It means that we have been able to heal our relationship without lots of other people picking at the wound.
I am sure you will get lots of support on here and I hope you can recover your relationship if that is what you decide you want.