No that I can say I have a valid response to this, having not been married before, but…….to put it bluntly if I were married and I found what you did, asked my husband what was up, had him lie to me, AND then kept conducting the same behavior it seems to me like you could have one of two general situations going on.
A) She’s a bitch, plain and simple. You’ve been married to her for a while, maybe she’s been doing other things that were slowly asserting her power in the relationship until it got to this point where she feels its okay to cheat on you. Just as many women feel over-entitled as men do.
B) (and most likely in my opinion) is that she feels like something is missing in the relationship and somewhere along the way, you two got your wires crossed and stopped communicating effectively, so she got frustrated and, rather than being a mature adult and just leaving, she decided to cheat on you.
What can you do?:
Go to her VERY calmly, very maturely, and state what you know. Theres no reason to be afraid, whatever happens you’ll be able to deal with it, you’ll live. Think of it this way. You’ve been together 8yrs, you could go on saying nothing and be unhappy for much longer OR you could work through things and be happy OR you could be free to be happy on your own.
Anyways, go to her, state what you know, and confront the issue. Don’t put things on her, don’t say “you did this or you did that” no blame game bs. Ask her what YOU did wrong. Ask her why she feels like she’s done this and what she felt like she was lacking from you that she could get from this other guy. Listen to precisely what she’s saying, don’t try to write it off as this thing or that thing. And then when she’s done, explain that what she’s done has hurt you a lot, but that you’re willing to work past it. Maybe try a marriage counselor, or just set up a specific time, every day, where you can work through your issues. Something like that, and you can give her a little time. If, however, things don’t work out after a couple weeks, she relapses, OR after telling you what’s wrong she plain doesn’t want to stay with you, you should get your things in order for a divorce. It sounds big and bad and scary but again, you’ll be far happier away from the situation that stuck in it for a lifetime.
