I feel for you.  When I was in high school I was rejected many times when I would ask a girl out.  I only had two dates in high school and neither girl wanted to go out with me a second time.  My self confidence was so low and my anxiety so high, that I froze and couldn’t speak in a coherent manner.  Each rejection dropped my self esteem even lower until I believed I must be defective in some way.  It became so painful that I gave up rather than take the risk of being hurt again.  I was a late bloomer so as my self esteem and confidence started improving in college, I felt more relaxed when asking someone out.  Doing things that improve your self esteem and confidence in one area of your life can carry over to other areas.  Rejection is still tough for me but at least its not a catastrophe anymore.