My mom has told me my life amounted to nothing, why doesn't my face look nice, I'm getting fat, why does my hair look bad, what good am I to the family if I couldn't give her a grandchild, etc.

She picks on me because she can. Don't all parents believe on some level, they should be able to do these things to their kids? I no longer think about the why. I want to learn how to deal with her and have her words slide off my back.