Eventually you will be grateful you didn't spend two more seconds with him. You should not feel bad. You are not the one breaking up the family. In my opinion if they cheat it is just too hard to trust them anymore. There would be the doubt every time they went out. In my marriage I felt like beer was the mistress. Mine drank Natural Lite and Miss Lite was the mistress. She won. But I have me back now 4 yrs. after my divorce so I won. You will heal in time. And no contact is wonderful. The more there is no contact the easier it gets. You have to a little with the daughter but less is more.