I can understand how you feel. Trust broken is very difficult to mend but.. not impossible! You can get through this but really if he's being as good to you as you say and has changed and left that all behind, he should be understanding as to how this is going to affect you for awhile. It's going to take work on his part to restore the trust. Really he's gonna need to work harder now than ever to show you that he's faithful and true. That's not a bad thing. You'll both come out with stronger character, and your relationship will be hard to tear apart again.

Forgive yourself for still feeling bad about it and crying and feeling betrayed, it's one of the hardest things to get over and it takes time.. be patient with yourself.