Seeking Relief from a Mother's Curse After Her Passing

Assalamu alaikum. My mother passed away three years ago, and I'm struggling deeply. She was a devoted woman who gave us everything, but she had diabetes and serious anger issues. In her rage, she would sometimes make baddua against me. I was a careless teen-lazy, mischievous, and I pushed boundaries. She warned I'd appreciate her only after she was gone, and I didn't listen. Since her death, our family's been hit with trouble after trouble. Financially, we're struggling. My father once had a good life, but it was ruined by black magic. He sacrifices everything for my education, hoping I'll support him, but I feel like a failure. I can't stay consistent-I have ADHD. I've tried praying my five daily prayers, making sincere tawbah, sobbing in sujood, but it's like my duas hit a closed door. I find no peace. I'm slipping into addictions, becoming someone I hate, and I feel powerless. I'm convinced this isn't a test from Allah or black magic-it's my mother's baddua. My dreams were never selfish; they were for my family's welfare and serving others, yet my life feels cursed. Dark thoughts creep in-sometimes about ending it all, sometimes whispers of atheism-but I know I won't act on them. I can't fight my mind forever. I just want to provide for my family so they can live comfortably. I need guidance from the Qur'an and Sunnah on lifting a parent's baddua when they've passed away. What kaffarah can someone without money do? What did the Prophet ﷺ teach about reversing a justified curse? I'm desperate for specific du'as, actions from the salaf-anything real. Please, if you have knowledge, share it kindly. I'm barely holding on.