I need help making my decision!!?

Me and my boyfriend have been together two and a half years, and he admitted that he cheated on me last year, and he told me at the worst possible time.. Christmas day!! He said that he had felt so guilty about doing it that it had been eating him up inside and he felt he had to tell me for us to be able to be together properly. Things were hard but we got through it. We have just broken up (like a week ago) and have still been talking. And now I have just found out that he cheated right at the start of our relationship. Like two months in. We have been talking about getting back together and now that I have found this out I need some opinion on what I should do because I am truly confused. I love this guy more than anything in the world and really want to give it another go, but Im unsure because of his past betrayal!! Help me please!!!!!