I was extroverted when I was little and in some circumstances I
  extroverted, but in environments with a lot of people, I would
  get anxious and shut down.. Too much input at once. [probably
  being 1/2 deaf, it was too much to try to make sense of all of
  it] I could "feel" the social pressure but was never sure what I
  was "supposed to do". When I *would* extrovert, I did it wrong.
  I'd be weird. Say a stupid joke. Do something dumb. Didn't have
  a thick skin. But I developed my thicker skin through the years
  somewhat and I can hold my own in groups better now. For me, I
  find extroverting on the Internet was the best thing. I can have
  the same depth I'd get in one-on-one conversations in real life,
  but with many people. More control. As long as I know what I'm
  supposed to be doing or saying, or what role I'm playing, I'm
  ok. It's when I don't have a role that I get lost in groups.
  Just being "one of the crowd" was always hard and spotlight
  "center of attention" was too much for me. But no complaints
  smile emoticon I like who I am and and try to help other ppl
  like themselves as well. It's a good role for me.