Honesty is very important in any type of relationship including friendship, I'd say.
I can understand hankster's point of view, but if you think the guilt will keep coming back, it might be best to come clean.
The alcohol issue, which others have mentioned, should be addressed. It didn't completely lead you to take those actions, but it didn't help prevent you either, did it?
I don't think you're a terrible person and the fact that you're considering his feelings is important. Yeah, things could go badly with you and your friends if so, but it would probably be better than them finding out another way and thinking that you not only did those things, but also hid it from them.
In any light, I say good luck. Hopefully things won't be as bad as you feel they will, but we're always here if you're ever in need of any support.