Lack of self-confidence is a self-perpetuating problem, and it's a huge problem for you, I'm not sure exactly why. Try to pull yourself up out of your depression, and things will turn around on their own once you start feeling better about yourself.

Also, and this is very very important for you to remember, self-confidence and zealotry are not the same thing. Self-confidence doesn't mean feeling like you have the only correct opinion.

Also please don't take this as criticism, it's supposed to help! (by giving you an idea of why you're depressed, I hope)