my parents see my health as a joke

As a kid I barely went to the doctor or ER. maybe like 3 times in 18 years time, because my parents didn’t allow me unless I was on the point of dying or someone else has forced them to go. All the times I’ve been to the doctors were either me bleeding out after a bullying accident and the school having to tell my parents to take me to the er, or when my dentist had sent me in for emergency surgery. When I turned 18 I took it upon myself to go to a doctor for all my complaints. Now about a year later I am diagnosed with different diseases which also include brain and lung diseases (not going to specify just in case one of my family members has reddit). When I came home with the diagnosis on paper they got angry and told me I was just acting as if I had those because no one else in the family does so it’s impossible. How am I supposed to act as if I have lung and brain diseases? But it’s odd because their other kids are treated as absolute gods. Literally stubs their toes and immideatly get rushed into the ER with ambulance and police forces and what not. Great example, sibling is tired so my parents go omg get yourself checked get your blood taken something might be wrong with you! I get ran over by a car, ambulance called in at home to tell them I would be home later because I was in a car accident. I get home and they tell me I’m overreacting and just acting as if I have pain AFTER BEING HIT BY A CAR. I don’t get it, why do they hate me so much? If I start about my trauma they start screaming at me telling me how much they’ve done for me and how ungrateful I am. My sibling starts throwing death threats at them under the excuse of trauma and they instantly baby them and tell them to get therapy so they’ll feel much better soon. What is it about me that they hate so much? Didn’t I meet their expectations from the second I was born and are they just trying to get rid of me without being deemed as bad parents or murderers? I just don’t get it anymore, in a big joke to them. I bet they would celebrate it if I were to kill myself, or they would tell me I was overreacting by being dead at my grave lmao. I just don’t know what to do anymore. And for anyone who’s going to “go live by yourself” I can’t, I can barely pay my bills as it is already and I’ll never get a house because everything is full already. The only option I have is sleep under a bridge somewhere, or kill myself