My mom is obsessed with being right?

when she's right, i let her be right. i can understand that being wrong is embarrassing and i understand it feels darn good to be right but she takes it to a whole new level. whenever we talk about anything, and she ends up being wrong, i try to point out why she's wrong she continues to defend the same point until it becomes a shouting match, one of us usually ends up in tears, and she is willing to do anything - scream, cry (phony tears), blackmail, berate me on a personal level etc - to be right. rather than forfeiting and accepting the knowledge gained from the person who is right she is willing to hurt both of us deeply and cause suicidal thoughts in me and generally make everyone in earshot less happy to be right. never mind that her daughter is spiraling into depression, never mind that the neighbors are awake at 4 am, never mind that im getting hoarse from all the shouting, all that matters is that everyone pretends shes right. she has a few last resort desperation moves she pulls when she runs out of good arguments, "that's my line" can be said in response to virtually anything "you are an abuser" she is the one who will do anything to be superior "that's a lie" in response to a natural angry tone (your tone is a lie), tears or confession of suicidal or self destructive thoughts, or when i tell her that i just want her to stop hurting me (im not hurting you you're not sad that's a lie) the thing is she doesn't consider it being right unless someone else is hurt. also every conversation turns into an argument so this happens maybe 2 or 3 times a day more if i don't consciously avoid talking to her i just don't know what to do, even if i let her be right she has to viciously gloat about it for longer than the argument takes, even if i agree im no better to her and just as worthy of emotional torture. im crying so much my shirts all wet, what should i do