I wish I had more helpful advice--you sound almost exactly like me. I had a relationship where I was cheated on and I did find that I used every excuse to throw tantrums, make him feel ****** about what he did, even months and months later.

What I did was I told him it was his fault for hurting me in the first plcae, and that he was the one who has to live with the consequences (my rage). This pretty much ended our relationship as time went by.

I would suggest that you come up with a list of things that he can do to better serve you. It would demonstrate his commitment to you as well as benefit you personally. Perhaps if he acts right and makes it up to you the rage will subside naturally.

I mean the evil part of me is saying that you should have an affair too, but that would probably complicate things. I do not give the best advice.

Offering solidarity, tho. It's a terrible thing.