Mom ALWAYS favors little brother?

I'm 12. And I know that "all" kids think this, but I'm serious. She yells at me constantly if i ask him to stop pestering me.She says that he doesn't do anything to me. He always does stupid little wrestling moves on me, and I have a bad knee and I can't afford to hurt it again (I play soccer). He calls me a slut, a , (keep in mind HE IS NINE!), and endless putting me down. When these things happen all she does is laugh and use a stupid little baby voice and tells him how cute he is. I'M SO SICK OF IT! When he does this stuff she just yells at me and says that he's not doing anything. Everyday she tells me to be nice to him, but it doesn't matter if he's nice to me! She tells me all I do is sit in bed and text. I hate being around him or her. I do all these chores and she says I'm lazy and selfish and I don't do anything. And of course he does everything and is the nicest brother in her eyes. I can't take it anymore and I hate this house! I'm not the only one who see's it. Just today several people asked me why my mom was nice to my brother and not me. Please help what do I do? I can't ever tell her how I feel because she just yells at me and says that I'm wrong then tries to make me feel bad. When I try to tell her how I feel the yelling starts and then she won't tell me that she loves me. She doesn't say that sshe doesn't love me. But when I tell her that I love her she won't say it back for days. I just want to leave this house. PS my dad doesn't live with us anymore.