I can somewhat relate to this. My mother was physically/emotionally abusive as well as negligent for most of my life. She developed dementia about five years ago when i was 14 and it has progressed to the stage where she doesn’t recognize anybody and is hopsitalized, doctors say she may last a couple more months at the most. She might as well be dead. I was always a very emotionally detached person but i think although i would mostly be relieved and happy that she died, a small part of me will be sad because even though she was a terrible mother, she was still just that. My mother.