I STRONGLY dislike my brother right now!? Parents let him?

I'm a girl and I'm 13. My 20 year old brother said I could walk to the pool a couple blocks away. He walked with me then when we got there my brother saw his friends and he stayed but I was with my boyfriend and I was basically laying on my boyfriend making out. But I'm not allowed to date. My brother got mad and made me leave early so we were walking home and my brother was yelling at me so I yelled "stfu and leave me alone, d***!" so he grabbed me and basically dragged me the rest of the way home and when we got home he slammed me on the couch and went and told my mom and step dad. He came back and told me to go to my room, I said no, he said I a's getting spanked AND grounded. So I yelled why. My mom asked me to listen to him so I said "okay fine but if I listen I get to go live with my dad!" so I had to go to my room, I slammed the door and locked it. My brother knocked it down and grabbed me, forced me over his lap and spanked me! He stopped when I was crying/screaming/begging him to stop. Then I hit him so he pulled my pants down and continued. My mom heard me crying harder so she came to my room and told my brother it was enough bcuz I was being too loud and they didn't want the neighbors to think abuse. I want to live with my dad now but idk if I can choose that! So opinions?