I know your going to want some answers, you wont get them, you certainly are NOT going to get answers your happy with anyways.

Keep yourself as BUSY as you can, join a gym, pick up or restart a hobby that you've given up, eat, make sure your sleeping best you can. Your mind it going to be taking you places that you don't want to go, so the busier you can be the less it will be on your mind. I'd often go down to the library, its free, you have a plethora of books to read that can help.

The hardest thing for you right now, is going to be to DETACH. Which basically means, you have to be able to forget about what your wife is doing, or in other words, focus on yourself.

Do some research here on the forums, read some people sitch's (situations) and get a feel for what your up against. Knowledge is power, give yourself some tools. Theres many stories here that will feel like they were written with you in mind. Know your not alone, vent here, ask for advice, journal to get things out. You'll find holding it back will only result in more frustration.

Do you have a friend you can confide in, please be careful bringing this up to family. They don't want to see you hurting, and some advice will be given seem like short term fixes, but in the long run, don't really help you out. That's what this forum is for, its a neutral outlet, we'll be honest with you to a fault, we'll smack ya with a 2 x 4, when your falling off the rails, but the advice will always be to help. We're here to help you try and save your marriage, not make it worse.