| | Re: I fell like my life just ended (long)
I've been cheated on a lot and it sounds like he's cheating. I doubt whether he has been unhappy since the beginning of your relationship. I think they say that to justify their affair, and somehow try to convince themselves of it.
You need to try to find some hard evidence that he is cheating and confront him about it. After that I'm not sure what you should do - I'm not the best person to give advice. I took back a serial cheater several times and I really regret it. But some people do only cheat once, and they are able to rebuild and improve their marriage.