Cheating advice

I found out my bf cheated on me recently and I'm going through all the emotions right now and can't make a clear judgement. I don't know what to do. He has apologized and told me he felt so guilty w her and didn't wanna ever do something like that again to jeapordize our relationship. He also reminded me how much he loves me and wants to earn back my trust. His best friend told me he wasn't sure he is ready for a relationship though. We have been together 3 years and dating 1-1/2 years. Advice would be greatly appreciated.