I'm sorry but that's one thing that I wasn't be able to do is forgive, she has totally no respect for you. That's something she should have talked to you about, before acting. It would have been better for her to leave you, than play like that behing your back,....and you know what, I've been there and it's hard, because he did come back and ask forgiveness and as hard as it was I said no even though I still loved him,.... now I'm looking back and I'm every happy with my life, I have an awesome boyfriend and we have a baby girl. I can tell you one thing it was hard to trust again, but I know that he loves and respects me, Hold on you'll get through it, GOOD LUCK
ps,... were you giving her enough sex,.... because alot of girls need it alot. just a thought....