I feel I've sinned and I'm scared Allah is displeased with me

Assalamu alaikum. I'm really shaken and I need to share this in the hope of some clarity. My mother physically grabbed my 7-year-old brother by his shirt and threw him. He told me he cried from fear. She's been snapping at him for weeks; I've overheard it. My mom abused me when I was young, so hearing my brother's story terrified me. Now she causes constant stress and chaos wherever I am. She also rarely prepares food for him. I'm unwell and can't cook - my doctor told me to stay in bed and avoid cold places. The kitchen is freezing because the house ventilation is terrible and the heater barely works. My only option is to stay in bed with a small portable heater. I went to my mother's room to ask politely for food. She snapped, “go make something, don't bother me.” I explained the only food available upsets my stomach and I'm already sick. Then she began shouting. When I asked why she was yelling, she spat out things like, “You're so annoying, I sinned having you, I wish you were never born.” I couldn't hold it in and said what had been building up inside me. In my anger I said, “I wish you were dead,” and “may Allah punish you for destroying the peace of this home.” She started reciting Qur'anic phrases after I spoke. I locked my door to try to end the confrontation. A little later she banged on my door and screamed insults through it, calling me names. I told her she must stop or I'll involve the authorities - I meant it as a warning to protect my brother and myself, not a threat. Now I'm afraid: will Allah forgive her because she prays, and will He protect her from worldly consequences? I want my brother to be safe, but I also feel that my mother should face accountability for what she's done to us. I'll never forgive her for the harm she caused, and my younger sister also refuses to forgive the violations she suffered. People say my mother seems mentally unwell; maybe that's true. But instead of seeking help, she takes it out on her children, then recites verses while the kids go hungry. I admit I was wrong to speak over her recitation - that's between her and Allah. I feel I've sinned by speaking in anger and disrespecting Allah. Is it wrong to wish for retribution against my mother for what she has done? I'm afraid Allah will chastise me by protecting her from the consequences I hoped for. Jazakum Allahu khairan for any advice or dua. Please keep my siblings and me in your prayers.