You may not be able to. I find that parents sometimes feel that children are not to share negative emotions towards them. My parents tend to shut me down if I try to complain about anything to do with how I was raised. I have been out of college for a decade! My sister and I still get shut down on the phone if we try to even remotely point out the effect that their negativity had on our self-esteem. Like you, I entered college without any self-esteem and had to be taught to think I am kinda sorta likable.
Advice? Hang in there. Work on getting out of the household. If possible, try to express self. If not (you are the best judge of this), find someone to talk with about it. This might make it easier to live with until you can move out on your own. Are you planning on going to college? If so, this is a great way to get out. How much time to do spend outside of the household? Are you still in school? Have a job? Participate in outside activities? It might help if you find a way to spend time away around others. Is there anyone who reminds you of your strengths? If so, you might try to focus more on what people outside of the home say about you rather than your parents.
As for self-esteem, my sister managed to realize that what our parents said wasn't a indicater of who she was. I didn't figure this out. But, it sounds like you have. I'd suggest that you continually remind yourself that your parents have some kind of issues that make it hard for them. My mom was raised by an overly strict father who was a pastor. He made them go to church a lot and spanked one of the sisters more than the others. So, your parents may have a bad childhood in their background. Of course, I'm only pointing this out as a way to try to remind that you can still be a good, lovable person even if you parents don't show it. You may be hard to live with like I was. But, you may be struggling with low self-esteem and other issues that just make it hard for you. Try to be understanding towards yourself.