Sick and tired of her opinion?

Okay, I'm the type of person that doesn't care what people think about me. I'm lazy, arrogant, I have bad acne and greasy hair and I just don't care! My dad calls me a grease-ball or grease-bucket and my mom will occasionally bash on me about my appearance. She often tells me, "I'm surprised you even have friends, considering how you have no hygine habits." That really hurts me. I'm sick and tired of her little "input" about my life. I can do what I want and if I wait a couple of days before I take a shower then so be it! I don't care that I have acne! I don't care that my hair is tangled and greasy! Why won't she just lay off and leave me alone? I get so angry when she says, "Go wash your face, your breaking out again. How can you have friends looking like that?" or "How can you have friends when your hair is so disgusting?" I'm sick of her sh!t! How do I tell her that?