I think you just have to remember we are our own harshest critics. We look into the mirror and see faults, see imperfections, see doubts. What you need to do is see yourself through someone else's eyes. What you see as imperfection or faults, they often see as unique and beautiful. One of my favorite singers is Stevie Nicks. Her voice would never win a singing contest, rough, gravely, an octive to low, and a bit too twangy. She could wish she had a "more Perfect one". But to her fans, her bandmates, her friends, they hear character, they hear raw emotion, they hear the someone singing with their heart. Not perfect but far better.
Doubts and fears can motivate us to work or try harder. There is nothing wrong with having them they key is accepting them for what they are and modeling them into what they could be rather than being obsessed about what they are.
And when all else fails......ask someone for a hug and let them show you how beautiful you are inside and out.