You find value in yourself by breaking the pattern your parents set for you. My father didn't interfere much in the way my mother raised me, but she thought/thinks that I'm a horrible person, a horrible disappointment, and she made sure that I throughout my childhood never got it into my head to think I was pretty, or intelligent enough, or good enough.
Truth is that she doesn't know me. She has no clue who am I.
It's taken me years to break free of the yoke she placed on me and I'm still working on it, but what fuels me is to prove her wrong. Not for her sake, because she'll never change her opinion of me, but for my sake. You might want to look into mind-reprogramming and how to let go of your past. Ask yourself, what can I do for myself RIGHT now that will make me and/or my life better, and then do it. One baby step at a time, and things will start to get better.
And yes, I do feel like flogging the parents who stunt their children in this way. Sometimes I feel like confronting my mother and ask her what on earth she was thinking? (Actually I know what she was thinking, she was thinking I was a terrible human being that need to be kept in place, so that my head wouldn't implode from arrogance and self confidence). But fact of the matter is that it's up to me to break free.