Dealing with Introversion

[Boolean]

Ever since I was in high school, being around new groups of people has made me somewhat anxious and extremely quiet. I've since gotten past the anxiety, but I've never been able to get past being quiet and being myself. When I'm around other groups of friends, I'll have a good time, I can relax and what not, but only when I'm extremely comfortable with them. I've boiled this down to a few reasons:

1. My inability to start a conversation (I'm boring, leave me alone)
2. Caring too much about what others think of me
3. Generally not wanting to socialize with the type of people around me

I wouldn't really care, but my girlfriend has noticed this and wants me to be more confident and more myself around other people as well. So I'm asking for some tips on how to break myself of this without using alcohol. What do you say to start a conversation with a total stranger or to someone your friend knows? I know the setting's probably important, so picture a pool hall, bar, or some other club.

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