When a mother's words cut deeper than anything else

Salam everyone. I'm struggling so much and I just need to let this out and maybe get some advice. My mum has been putting me down for as long as I can remember-since I was a little kid. It's like I'm her emotional punching bag and nothing I ever do is good enough. When I was a teen, I tried to talk to friends about it, but they didn't believe me because she always acts so sweet in front of others. I remember once my cousin had a falling out with her, and I tried to help my mum stand up for herself. She thanked me then, but later she turned on me and said I was stirring trouble. I just can't win with her. She's always criticised my housework. Even now in adulthood, if I clean something, she'll redo it and make a point about my 'low standards.' Last year she came back from a trip and immediately started mopping, even though she was exhausted, just to show me up. My dad and sister told her to rest, but she didn't listen. When I was younger, she would make awful comments about my body, saying I had no shape. It pushed me into heavy lifting and I ended up with an eating disorder and body image issues that I still carry today. She'd casually tell me I look like a drowned rat if my hair was wet, or call me a scrubber if I didn't wear makeup. But when I started wearing more makeup and considered a nose job, she said I'd never be happy with how I look. She tells me I'm beautiful, but then destroys my confidence in the same breath. I was bullied in school for my looks, and she knows that, but still keeps at it. I confronted her once about all the hurtful things she's said-like telling me I'll never amount to anything or that I can't keep relationships. She denied it all and made me out to be a liar. My whole family turned on me that time. I've confided in her about my struggles, like bullying and failed potentials for marriage, and she uses it all against me in arguments. Even my teachers bullied me in school, and it feels like everyone just tramples over me. I've tried to forgive her so many times, but she always goes back to her old ways. Just today, I helped her fold a tablecloth, and she said, 'You're not good at anything, at least be good at something.' I've dealt with anxiety and depression all my life, and she knows how much words affect me, yet she uses them like weapons. Last year, I was going through a rough patch after a relationship ended, and my mum made it all about herself. When my dad asked her to comfort me, she burst into tears saying, 'How do you think I feel? You're putting me in an early grave!' And he comforted her instead. He's a pious man and I don't want to upset him, so I keep quiet about what she really does to me. One day, my sister told my mum that a guy approached me in town. When I got home, my mum said I dressed like a tart-but I was in a baggy hoodie and minimal makeup. Another time, when I was getting to know a brother for marriage and told her about it, she later called me something horrible when it didn't work out, even though she knows I've upheld my chastity. It hurts so much. I once brought her a donut as a kind gesture, and it got squashed in my bag. She scowled. Then I made her coffee, and she said I should at least learn to make it properly. I cried so much that day because it hit me: even my kindness gets thrown back at me. I'm already heartbroken over someone I was talking to for marriage who ended up treating me badly and then just disappeared. On top of that, I have my mum's daily cruelty. Yet she always says she prays for my success and health. It's so confusing. My aunt on my dad's side sometimes puts my mum down in public, and I used to think it was her karma-my grandmother did the same to her. But my mum never sees the parallel; she just complains about my dad's family. I almost felt glad when she got a taste of her own medicine, as terrible as that sounds. I come from a strict South Asian background, so I can't move out until I'm married. I feel trapped in this house. She even befriended a girl who bullied me in high school and tells me to just get over it. Last week, I was vacuuming and she hit me on my side, hard-it stung a lot because I'd micro-needled that area before. She didn't care, just yelled about disturbing my dad's meeting, and later smirked when I said I was in pain. I just need advice on how to cope. Every day feels like the worst day of my life, and my mum makes it so much harder. My younger sister sees how badly she treats me but never stands up for me. I feel alone. She treats my other siblings better, especially my brother who has diabetes. I even remember her mocking me about losing a job once. I'm so tired of feeling broken. Has anyone been through something like this? What can I do to protect my heart and still be dutiful? JazakAllah khair.