Physically abused by brother

(im a 19F) Me and my mum get into fights a lot. Its mostly cuz of my brother. She always treats him like the prince he is and she rarely ever gets mad at him, and when she does she just stops talking to him and he sits at home doing absolutely nothing and doesnt get shouted at after that. For me she will hit me, like bad and then shout and degrade me and whenever she sees me not working she'll degrade me some more. Today i got into a fight again and he came in between and didn't allow me to continue my argument with my mom cuz she was like i dont wanna see her so he blocked the way so i pushed him and tried to go in. He is really strong and bigger than me. I managed to get in the room but he pushed me to the ground and had me in a chokehold for a good 10-15sec (i have asthma) and my mum was trying to push him away but when he did she hit me on the face cuz i was shouting at her for what he did to me. We were a distance away and i picked a metal bottle and threw it on his back. It didnt even give a scratch. My mum came picked up the metal bottle and hit me so hard on my elbow. It has a bruise.

I am in so much physical and mental pain.
If you're gonna tell me to contact someone, i cannot do that its out of the question. I need tips for fighting back. Getting stronger. Im moving out soon anyways but it stil hurts. I had thoughts about just ending myself and it gets stronger with each fight we have. I dont know how long i can hold on anymore