I'd never leave a friend for negative reputation which that friend doesn't deserve. It's happened to me though, after running away and returning back home, nobody really wanted to be my friend anymore. Yet if I could choose, I would have done it again, I don't regret that decision at all. Now I do have a negative reputation, but inside my home my life is nice which I never could have had, if I woudn't have ran away.
I've often had heard things against people I liked, but I always used to refuse to treat those people negatively because of that. Not unless I had seen my friend really do something awful. No matter what people would say.