So, I think I have figured out my problem.
Recently I have joined a bunch of groups because I'm finding things I enjoy and doing them. Which seems awesome, and I'm all excited about it, until I remember how ridiculously awkward I am and the fact that there are people in these groups who I don't know, that I will have to make friends with while pretending to be a normal person. No easy feat. So I tend to skulk at meetings, in the back, or leave early because I hate having to put myself out there.
And I have figured out why: I think I come from a place where I assume people don't like me. Which, you know, is totally great when they do, then it's like this great surprise, hey, someone thinks I'm great, and if they don't then really, I never expected them to anyway. The problem is when I am forced to meet and greet I assume I shouldn't bother people and should just leave them to their lives. I need to get over this. I blame a childhood of being too well-read for my own good and not having very many friends.