mom rant, not a good one

This really sucks, today is Mother's Day and my mother is pissing me off. I made a previous post about her and how she treats me like I'm her slave, she disrespects me and my boyfriend. I asked her for a haircut and she said "why don't you ask your boyfriend to pay for it" like he's made of money? (I'd pay but I'm still looking for a job). I go to my boyfriends every weekend and the semester just ended for me so I thought I'd stay a little longer, I'm 18 so it's not a "problem" and I've done it before. Anyways, my mom texted me around 11pm to bring my car home so she can use it for work even though there's 3 perfectly good cars at home, there's a 2008 pathfinder, 2015 Toyota Sienna, and an old truck that still works fine, but no god forbid she take her own car to work, she has to use mine, and if I say it's late and I don't want to drive ( i try not to drive at night bc other car lights kind of blind me and my vision gets blurry and I've told my mother this many times) she threatens to take away my car even tho she's not the one who bought it, or even pays for it, my step dad does. Then she continues to tell me how selfish and greedy I am even though I sacrificed so much for her, I have 4 younger siblings, I stayed home all the time to help take care of them, I had no social life, couldn't do any after school activities, I kept my grades up, and senior year she asked me why I didn't get into any universities, gosh idk maybe it's because you forced me to come home everyday day right after school and if I even thought about being in a sport or club it was selfish bc I couldn't be home to help. When I was 16 I found out she was having an affair and when I confronted her, she started talking to me like she was in high school gossiping about boys, I love my step dad like he's my real dad, I didn't wanna hear that crap. When I told her that she said I was overreacting and it's "normal", but fuck all her secrets and her making me not say anything was eating me up and it was overwhelming and I didn't know how to deal with it, I got really depressed and I dropped like 20 pounds in a month from not eating, after a few months I tried to off myself. When my mom came and saw me she yelled at me, and after I went to the hospital and a few months of therapy, she started having another affair and continued to talk to me like it was gossip even tho that's what pushed me over the edge last time. She just treats me like I'm not good enough to be her kid, she makes me feel like I'm a bad person, she said it's selfish for me to go to college (community college) it's selfish for me to get a part time job, it's selfish of me to not want to drive late at night and to question why she couldn't use her own car. My siblings aren't babies either, they're smart little elementary schoolers, 1 middle schooler, they don't need me around 24/7 anymore. She makes me feel so bad about myself, I've been pushing all my negative feelings/thoughts behind a door and she just picks the lock and sometimes I feel she tries to push me over the edge, purposely. It's so hard to deal with. My biological dad left my mom bc she was pregnant with me so I'm starting to think she resents me in some way. Idk what to do with myself anymore. Sometimes I think it would be better if I was gone, but I couldn't do that to my siblings or my boyfriend.