I love my mother, but I secretly pray she passes away in her sleep every single night

For the past three years, my life has been reduced to caring for my 78-year-old mother who has severe cognitive decline. I had to quit my full-time job, move into her spare bedroom, and spend eighteen hours a day managing her medications, cleaning up accidents, and listening to her scream at me because she thinks I am an intruder. I am thirty-two years old and I have no social life, no dating prospects, and zero savings left. My two older brothers live across the country in high-paying corporate roles. They send a hundred dollars once in a while and call on Sunday afternoons for five minutes to give me condescending advice about "being patient with mom." They have no clue what it feels like to spoon-feed pureed soup to someone who stares through you with dead eyes. every single night when I tuck her in and close her bedroom door, I find myself wishing she doesn't wake up the next morning. i feel like an absolute monster the second the thought enters my head. She sacrificed so much for me growing up and she did not choose this illness. But the physical and mental exaustion is completely killing me from the inside. I just want my life back and the guilt is suffocating.