Well, I'll tell you one thing- you're not unfaithful to anyone you haven't committed yourself too, so that might help with that.

[It's a bit silly, in his mind, to think that way.]

This is going to sound really corny, so I'm just gonna come out and say it- you have to do what your heart tells you. If the guy is that important to you, and you're willing to wait for him, then you shouldn't do anything here. But I don't think there's anything wrong with wanting to be with someone else, either. If you do anything less than what you want to, you'll just be unfaithful to yourself. And that's worse.