My question to you is, why don't you have confidence? We're atleast 21+. We should realize life is full of downers and negative people and these are the people we should negate from our lives. Be positive and that should make a lot of people want to be around you. Don't worry what others think of you. I've always thought that if someone has time to talk crap on you, they are the ones that have their own problems and it shouldn't affect you.
Practice introducing yourself to others and not wait for them to do it or until its too late. Build your network. Eventually, it'll become normal to you. You see new people around your group and you'll naturally say "hey im ________. " "how do you know ______?" "are you having fun" ' do you come here often?" "what do you do? work ? school?"
It's not hard and people will feel comfortable around you for initiating it the convo.
I live by these five rules:
1. encourage others. encouragement goes along way.
2. appreciate others.
3. forgive others. don't hold an emotional burden by holding a grudge. you actually waste more energy and feel worse by doing this.
4. listen to others. simply, listen to others. people like being listened to, just like you. be able to give feedback, not just " ohh i see " or "uh huh"
5. understand others. understand what other people are going through and don't judge
It will eventually come back to you and someone will do the same for you.