That happens to me a lot when I'm depressed, more so now then when I was younger. I actually don't feel comfortable unless I'm in a quiet room with the world shut out. Other symptoms are lack of interest in things you commonly enjoy, self loathing and extreme lack of energy.

I wish I knew more about why this anti-social behavior is a common to some BP's but I don't. All I know is that I have the same problem at times.