Should I stay with my boyfriend even though he cheated on me?

I recently found out that a few months ago my boyfriend cheated on me. We've been together almost 2 years and I do love him. I haven't tried to retaliate or even really like tell him that I know what he did. He hasn't owned up to anything either so my trust in him is kind of shot. The person who told me is his brother's girlfriend and I have no reason to doubt her because she told me the same exact story that someone else had told me. She also said that the girl that he cheated on me with was trying to hook up with him again but he wouldn't have anything to do with her. I'm just confused I'd like to confront him with it but then I think "If he didn't want to be with me then he wouldn't" I may be wrong but I don't want to wait around and see if he does it again. But I also don't want to leave him either.