When it comes to socialization, I have always gravitated towards people whose friends I like. A celebration at someones home where most of their old friends and a few of their new ones are invited is usually a good gauge for whether I would blend in or clash in my host's social circle. Every time I have second guessed myself and decided to give it a shot despite feeling the clash vibes, I have been disappointed. Who knew there was a scientific basis for all of this.
Recent research shows that our moods are far more strongly influenced by those around us than we tend to think. Not only that, we are also beholden to the moods of friends of friends, and of friends of friends of friends - people three degrees of separation away from us who we have never met, but whose disposition can pass through our social network like a virus.
I am totally willing to believe that there are certain personality types that will clash even if they don't interact directly. The influence rubs off on those with who they do and can manifest itself in the other person sometimes even without their knowledge.