This has happened to me, too. People gossip and put down another person whom I haven't met, and then I do, and I find I like the person, or at least, don't dislike them. Sometimes I've befriended a person, only to find out later, the others were right. But I don't let anyone tell me who to be friends with, including my friends. If my friends didn't want to hang with me because I was friends with someone they didn't like, or if they refused to be respectful when around that person and me, then they wouldn't be my friends anymore. That's not my choice, it's theirs. My dad taught me that while I was very young. My friends don't have to like each other, and they don't have to hang together (even if I'm there), but that doesn't mean I can't hang with all of them, even separately. Yes, that can pose some inconveniences and even some problems, but I pick my own friends. I don't tell my friends who they can hang with, and I won't put up with them telling me. However, I will warn them if I think someone will deceive them or treat them badly, and I appreciate them warning me. It's something to keep in mind, but you can still keep an open mind about a person.