I'm not at all a social person, but I get by through acting. I pay attention to my speech and mannerisms when I'm at ease with friends and family. In stressful situations, I act like myself.
It sounds so crazy, but once you emotionally disengage a bit from a stressful situation, it's easier to relax. When you relax, conversation is easier. Then, at some point, you find that you're actually enjoying yourself and conversation is fun.
