I'm 23 and I've left small jobs due to my anxiety. I also had a very crappy childhood, loads of emotional abuse and really messed up situations. I'm currently in the process of looking for full time work which means going on tons of interviews and taking pre-tests. It has boosted my confidence just to know I am more than capable of doing these things. I know the area that I have to work on, and that is not taking other's opinions of me too seriously. My anxiety stems from how others are perceiving me. If I could learn to just stop caring about what other people think about me, I know I'll be much happier. Its definitely a confidence issue. But you can always get up and try, try again.