I'm glad you've developed some numbness. That is the very best thing you could do. Your parents don't deserve to have their assessment of you taken seriously because their comments are never based on a good faith effort to be constructive. Oddly enough this may be coming from a desire by your parents to keep you from ever leaving them. If you have no self-confidence, you'll be afraid to venture off anywhere.

So not getting married is the worst thing? They see getting married as the proof that someone has worth? Lots of jerks get married every week. Maybe you will and maybe you won't, but that's not proof of anything. Some of the worst people on the planet are married.

You have to get away from these two, either physically or at least mentally. If you can make enough money to support yourself, leaving their home would be an excellent idea. If you can't afford that, then you have to insulate yourself, psychologically, as best you can. Find things to do that get you out of that house.

Your folks are never going to change. It's sad. But you are not who they say you are. You have capabilities that you, yourself, would be surprised at. Go to school, or work hard at whatever job you can find. That way you can become your own person.

Your parents are losers.