I'm in a black hole in my life. Please don't judge, just help me. Thank you!...?

I'm a huge brat to my mom but nobody else, (my teacher’s have always loved me.) We get in wicked fights where I am very mean to my mom. I verbally/emotionally abuse her. I grew up without a father figure and it was pretty much just my mom and I. She’s a young mom, (only 20 years older) and she played the role of a friend or sister more than a parent because we grew up in rough times, but regardless she always provided for me and made sure my needs were met. (We were on welfare for a couple years, she’s been divorced twice, my dad’s an alcoholic, her parents died.) I think I grew up knowing that I could get my way by treating her badly. Even last night I called her a “dumb b****” because I was feeling poorly about myself for missing classes that day and I felt that my life was already going down the drain, so yelling at her wouldn’t make much of a difference, I was already a bratty loser. I feel that there’s no hope because I’ve been a brat to her since first grade and I have always labeled myself as a bad daughter in my mind. Plus, I will immediately feel bad after an argument, but then I know that I’m not stable enough to be able to count on myself for changing my ways in the future, its just like a huge bad habit. Today when she came home from work, she told me that it was so depressing with me at home. It affects my relationship with her because even when we aren’t fighting, its awkward and it feels fake and I get annoyed with her, and I’m short-tempered and get depressed around her. I don’t understand why I’m like this. This side of my personality makes me hate myself.