I feel for you hrich, I have people in my life that try to knock me down as well. It's very frustrating. It makes me want to go try to knock them down. But I'm really not that kind of person, I'd rather build someone up. If you feel you don't deserve it, just remember you don't have to take it. Try to work on ways to confront it when it happens, like "You know, I really don't appreciate that (smartass) comment." If you do it enough times, eventually they should get the message. You've got to do whatever you can to take care of yourself, especially if it makes you want to drink.
You could also try talking to a professional about this stuff, that can help.