It is never okay for your mother or anybody to hit you, threaten you or verbally abuse you.

When my son was a teenager he was defiant and had temper tantrums. One time I wanted to smack him because I was angry but I knew he would not learn anything if I resorted to that and I had to leave my house and drive around on the interstate for a couple of hours to calm down before I could deal with him. He was trying to provoke me to anger and indeed I got angry but I chose how to deal with my anger.

Name calling is verbal abuse. It is okay to criticize a person but it should not be done in a hurtful way. Your mother is hurtful.

The first thing you need to understand is it is not your fault that she is dysfunctional. The second thing is how are you going to deal with it. How old are you? Do you have any other family that you can talk to or perhaps spend time with? Perhaps you could talk to a counselor at your school and ask for ideas to help.

Keep posting here but log out when you are done posting. I don't think it would be a good idea for your mom to read your posts right now. Maybe at a later time with some support you can talk to her but she doesn't sound approachable at the moment.