Hi Space, I'm sorry your life is so difficult at the moment. I can relate to the effect your upbringing has had - my parents spoke similarly to my brother and I, although I think it was with the intention of motivating us to prove otherwise rather than believing we really were incapable of achieving. Rather counterproductive though.
I'm not sure if you've already come across it, but SENG has some articles that you might find helpful.
Re your comment about external validation - I disagree - I think it's important to get this from somewhere. You can spend an awful lot of time trying to reason out a solid rock of truth and meaning to anchor yourself to and measure yourself against, but never find one, particularly if you're heading far into existentialism. Then of course you have no way to confirm your worth, and it seems to me that you badly need some affirmation.
I second the advice that ColinsMum was given - just do it. Make a leap of faith - choose something you're interested in, head into the world, and see what happens. Absolute truth is hard to come by, but that doesn't mean you have to miss out on discovery, excitement, love, beauty, hope, adventure.
I know it's easier said than done, especially when you're young and living with your parents. I wish you good luck.
