I made a rule for myself a long time ago. If I'm not doing anything and I get invited someplace I'll do it. No matter how bad I think it will be. As long as it doesn't cost me to much or will land me in jail, I'll go.

You WILL find people you like in groups you don't.

I'm not saying you do this and it sounds cliché, but give people a chance. I used to dismiss people for not liking XYZ, thinking XYZ is cool, or other snap judgements. Also stupidity is not a character flaw, don't dislike people for being stupid. Ignorant yes, stupid no. Over the years I have met many good people that aren't very smart. Remember stupidity is genetic and ignorance is a choice.