My (26f) brother (18m) does heinous things and my parents are totally complicit

I used to be really close with my brother, but recently he has displayed behavior that has completely driven me away from him. From the beginning, he has had issues. Kurt was 9 when he was diagnosed with OCD. Our dad was a typical sports-dad and was way too hard on him when he would play soccer. Dad got kicked out of many games for being too involved in a child's game. I remember the two of them having screaming matches while practicing in the backyard. I believe the combination of trying to be good enough for our dad and his OCD set him up for much difficulty later on in life. A few years later, our parents had a messy separation and a divorce because our mom had an affair. I should mention that I had my own issues from this, and I am and always have been empathetic towards depression, therapy, and mental health. Anyway, Kurt really struggled when he moved out our house to live with my mom (myself and my oldest brother stayed at our house with my dad, not necessarily by choice but because it was easier than moving.) He started to gain a lot of weight from the medication he was on for depression and OCD, which greatly affected his soccer abilities so he quit. High-school came around and by year 11 he had virtually no friends. I'm not exactly sure what happened, if he was bullied or he was the bully, it was never really clear to me. What he told me is that his friends from soccer ditched him. But he has told me a few stories that sound like he was the one doing the bullying, and his old friends ditched him for good reason. My brother was totally unhinged from age 15 to current. He has an insanely short temper and he has been violent with my mom a lot. He will grab her arms, and he has hit her before. He calls her terrible names. He disrespects her until she cries. He will laugh at her crying. He throws things and has damaged many things in her house. She has called the police on him a few times. Kurt has called me terrible names, too. No one has ever talked to me the way Kurt has. But I have always understood that he is mentally ill, and that it isn't really him talking that way. I always forgave him. I have always told him that I love him and that he means the world to me and I'll always be there for him. But recently, I am ready to go totally no contact with him.

Kurt has a brand new 2017 car that my parents got him for christmas. When I was his age they got me one also, I still have it. I asked him if he would like to go to a fair with me, I was planning on going alone but my mom loves it when I get him out of the house. She asked me to let him drive to give him some practice. So we are off, and there happens to be traffic and a police officer is orchestrating it in the middle of the street. Kurt gets so close to hitting this police officer that it SCARED ME. I told him he needed to be really careful in this area, and to be especially careful when someone is in the road. He told me to stop telling him how to drive. I said I have a responsibility to make sure he drives this car safely being his older sister and also he ran through a stop sign 3 weeks ago and hit another car which made his car insurance DOUBLE! He started berating me on how I am not a perfect driver, and when I had a car accident 5 years ago, it was my fault (it wasn't.) He called me a dick. I told him to turn around and take me home because I would not stand for being talked to that way. I'm looking down at my phone because I do not want to argue with him while he is driving. He stops the car and I look up, we are in the middle of nowhere and he tells me to get out of the car and uber home. I yell at him to take me home right now. He begins to drive his car very fast and erratically down a narrow street. He looks over at me and says, are you scared yet? Just let me know so you can get out of my car. I texted my boyfriend as it was happening and he told me to get out of the car so he could pick me up, which I did. When I told my parents what happened, they were angry on the first day. But Kurt is still out there driving his car, and I never received any apology, which I didn't expect anyway. Kurt told my dad I lied about it, but my dad believes me. So when Kurt comes over my dads house, I don't talk to him, I don't even look at him. He laughs loudly with my dad and does so to show me that he doesn't care. It's fine, I'm in nursing school right now so I don't really have time to care about Kurt. Life is easier when I don't have to worry about him.

I'm in nursing school and I don't have a lot of money. Tonight I went out and bought ingredients to make my own pizza. I came home and Kurt was with my dad watching sports. They watched me come in with groceries, make and assemble a pizza, I cooked it and I went upstairs with my 2 slices. My dad texted me if he could have a piece, I said go for it. About an hour later I hear my dad yelling at Kurt and then I heard Kurt leave. I look around and my pizza was gone, apparently Kurt decided to eat the whole thing which I was planning to eat for lunch the next 2 days. I'm pissed, so I text him that was incredibly disrespectful and he owes me $10 for my ingredients, time and effort. He responds, "lol" and my parents tell my to knock it off. My mom said, I'll give you $10. I don't want my parents money, I feel so stupid for being so angry about this but its downright enraging. My parents are not any better than he is because they continue to support him through all of his disgusting behavior. I'm scared for the kind of person he will be become. I want to be a good sister, and I know he has a lot of struggles, but I can't let someone treat me so badly. Is there any hope for someone like Kurt to grow out of this behavior? How can I modify my own behavior so that I am not put in situations like this? I'm afraid I'll never have the relationship I want with my parents because I'm so resentful that they have let Kurt treat me (and them) so badly for so long.

**TL;DR;** : My brother displays acts of violence and disrespect often enough to warrant a no-contact,I feel completely alone in dealing with it, and my parents often victim-blame me when I tell them about it.