I have a crush on my best friend... who just broke up with his girlfriend?

I have a crush on my best friend, but the only issue is that he just broke up with his girlfriend. We know everything about each other and we get along perfectly. I have a feeling that he likes me too, but in my mind, I'm scared that he'll run back to her because she's been crying about it lately and he's too sensitive to hurt anyone. He broke up with her on Saturday because he was away from her for a week and he lost all feelings for her (I don't blame him, she's really really mean to him and keeps him on a really short leash and gets mad at him all the time for no reason.) She went over to his house and they talked about it because they wanted to be sure. He was more for it than she was. He left on Sunday for this week to be a counselor at camp & I'm afraid she'll snatch him up when he gets back and convince him to go back out with her. Should I tell him how I feel when he gets back? Should I let him go? I like the first choice better even though it's harder... I just don't want to ruin our friendship but I also don't want him to go out with her because she's definitely not the right one for him.