The only way I was able to get through high school was to convince myself and others that I didn't care what other people thought about me. Deep down, I really cared whether or not people thought I didn't care what they thought of me... It worked on the outside, but didn't really help my confidence any. It also shifted my own attitude to "I don't care about me". For a few years this went so far as to stop caring for my health and appearance, to the point where I realized my "life" had become a matter of existence instead of experience. Like things would happen, and I would be there, but I wouldn't consider myself involved. I wasn't "living", I was alive, but otherwise really kind of dead.
Back then in high school I could get away with being weird because "I didn't care if people thought I was weird". That awkward punk kid had two convenient excuses for not fitting in: 1) I was actively trying to not fit in, in order to fit in; and 2) I was a teenager so it didn't really matter what kind of stupid stuff I did because no one really took me seriously anyway. At the time I'd have never admitted or even realized that, but it's painfully obvious now that I'm looking back. I'm a little bit older and a lot more aware of what I was trying to do at the time.
But now I'm in the real world, this isn't high school anymore and I'm starting my career. So now I'm very much aware of how I do truly care what others think of me. This is good for my work life, and I am benefiting from that extra care, but my social life (such that it is) is paralyzing. I'm constantly over analyzing every situation and conversation, always second guessing my words and actions. Throw in my greater awareness to my gender identity, and my anxiety is building again to be as bad as it's ever been.
I guess my end goal is to find some kind of healthy middle-ground, between my overly nervous attitude now and my previous overly callous front. I just have to figure out how.