I've gamed with strangers (to me, though some of my friends knew them) on a couple of one shot deals. Otherwise it has always been either family, friends or people with whom I am sociable and friendly (church members, colleagues, co-workers, etc.).
I've never gamed with someone I didn't like or, to my knowledge, didn't like me, and can't imagine that would have any draw for me. So I just wouldn't do that, it would be better not to play or do something else, than for me to play with adversaries (in the bad sense of the term - I could easily play with competing adversaries that I liked) or hostiles. To me a role play game is about cooperation, achievement, and fun. It's hard to imagine accomplishing any of those things with someone you really disliked, or who really disliked you. (Of course, there's not a lot of people I actively dislike unless they are involved in harming others or in criminal activity, then I doubt most of those people would be playing RPGs anyway. It wouldn't be a priority activity for them.)
Now I have, over time, become real close friends, or better friends with people I have played with. But I can't recall any relationship going south over the course of play.
I'm generally pretty easy going and it seems to me that most of the people I've ever played with have the same general attitude.