Am I wrong for holding 6 years of anger in ?

When I was 12 my family use to abuse me mentally and physically. Now that I’m 18 I want absolutely nothing to do with them. I actually want them dead. I was the youngest in the household it was my parents my 3 half sisters (which I almost died calling them my family) and my oldest sister girlfriend. They all abused me all of them for little to no reason I literally remember getting beat bc my friend gave me a ride home bc they didn’t come pick me up I drunk bleach that same night. I wish I could recall all the times I ran away and attempted suicide but it was way to many. I’m not going to tell my whole life story but I guess from all the abuse I became absent minded and things were normal we were a normal family birthdays were cool and everything. Fast forward , every now and then I’d flash out on them “for no reason 😒” no I don’t need a shrink and I’m not about to tell them how i feel they know what they’ve done. I also hate the fact they get so offended when I don’t introduce my boyfriends / friends to them like I’m not even sorry I don’t want anything to do with you. I just needed a place to stay I never did claim them as family we just communicate and laugh. I hate them they have no idea how they ruined my life. Idek why I’m so nice to them wtf is wrong with me.