I can't take it anymore.

I have been self-harming for the past two years and I want to go get help and to get a diagnosis from a therapist for several things (depression, bpd etc.) but I can't becuase my parents don't know anything about it. I can't tell them becuase my mother constantly belittles other people with mental illnesses in front of me and she says that those people need to getter better before they get mental illnesses (I don't know, it doesn't make any sense). She has also laughed at me when I once gathered up the courage to tell her that I think that I might have depression (about 2 years ago) and I was going to tell her about my self harm but then she was like, "Where did you learn this? The internet? You really are stupid enough to belive that stuff?" So I denied everything that I said. I relapsed today (for self-harm) and I feel terrible. My parents are constantly telling me to be better, and to be faster than other people. My mom screams at me when I want to have some alone time (she says that I'm wasting my time) and whenever I disagree with her on just about anything, she starts to scream at me, then she literaly denies that she even said anything. She once told me that the world woudn't care I died and she has never once apologised. I'm scared and alone. I don't want to self diagnose becuase I know that it's bad and that it's frowned upon but I really have no choice. SometImes I tell myself that I'm just looking for lables and that there are other people that are seriously harmed by these things but other times I feel so mentally depressed. I put on a mask everyday (mostly back when I still had school and before corona) and no one really notices. My ex-best friends mother died a few days before and I don't know what to feel. I didn't know her that well but I still knew her. I mean I went over to her house a lot before and she was always really nice to me. I just don't know anymore. My head is always so loud.

Sorry for the rant. I know it probablly doesn't make any sense and everything is jumbled toghether. I'm also trying to sort out the thoughts in my head. I was in a rush to finish this becuase my parents also don't know about 7cups and if they did, they would probably take it aways. Anyways thanks to anyone who bothered to read through this, it means a lot.