I know how you feel man in terms of psychological sensitivity, I was bullied VERY badly for pretty much my whole childhood, sometimes the negative beliefs do creep in but i've gotten good at filtering them out
Fact is you have to condition yourself, if you get rejected use it as exerience instead of beating yourself up, reflect on where you went wrong during the interaction and in your next interaction correct it. As Tyler Durden says, hell if you approach enough most of this shite will auto-correct itself! Address all your problems and sticking points, face them head on and make an honest and whole-hearted effort to strip away the inhibitions and negative beliefs about yourself that you never asked for but were beaten into you by social conditioning. Ignore social conditioning altogether and never seek the validation of others, validate yourself instead. I'm not going to lie, I still have trouble following these pieces of advice but so far they've done pretty fucking good by me, Rome wasn't built in a day, it'll take time.