My b/f cheated on me, but desperately wants to remain friends?

I was with my b/f for 6 months in a long-distance relationship.He is 30 and I am 27.I went to visit him in Germany recently since he is stationed there and I currently work overseas, where I just happened to meet him before going back to Germany.Well, I happened upon a dirty video he made with his supposed "platonic" friend that he had talked about off and on for months,while he went to work one day.I noticed even before I arrived that he started pulling away from me, and that just confirmed my suspicions.He admitted to sleeping with her twice,but of course I'm thinking it could well possibly be more.I ended up going to Greece for a week to clear my mind and I was able to forgive him,but I still love him,too.He said he wanted to at least work on our friendship and that he would be heartbroken if I considered cutting off all contact with him.Just out of pure spite I want to hurt him like that,but I know two wrongs don't make a right.I am so torn on what to do.I love him and we were really good friends before we fell for each other.But he knew from the beginning how hurt I was in the past,and he made all of these promises that just seem all lies now and were not kept.Why is he wanting to remain friends with me?He says he still loves me but my feeling on that is if you truly loved me you would not have done that with her,and reured me she was just "platonic"! I feel so betrayed,and never thought he was capable of doing that.He seemed like he truly was genuwine and different from the rest of them,but I guess all guys say that to try to get you.I feel like I need to at least dissappear and distance myself for a while,but not sure if that will only add strain or actually help things.Any ideas on what to do?I am lost and confused and torn on everything right now.Thanks guys.