How can you have a social life in Houston when you’re broke?

I've never been one to go out much and I've always been a bit antisocial. As a result, I don't have many friends or had any serious relationships. Lately, I've been feeling sad and lonely, so I want to try getting out of my shell and become a more social person. I want to meet people and make new friends. However, I'm not really sure how to go about doing that. Clubs and bars? I can't really afford those places. I feel like I don't have any options when I'm broke.