My parents act like they don't know I'm depressed?

I amm very paraniod and depressed. I cut myself and wear black and listen to loud screaming music. I stopped caring about everything, my room is a mess and all of my "friends" are like me. I think the reason I do this stuff is because my parents are always yelling and my mother has just gotten better from cancer, but it wasn't bad cancer and she didnt need chemo or anything. I feel llike shes using cancer as an excuse to yell at us. When any of my family members talks back to her she yells and says she doesnt want to be treated like **** by us anymore when she is the one treating us like ****. When I tell her im depressed, she just yells and says to stop with my dramatics. She doesnt even see the scars from my cutting even though they are in plain sight. Please do not tell me to stop cutting, that is not what I want to know. I want to know what to do about my parents and why they dont give a **** about me or my siblings.