When I was in a situation like yours what finally worked is for me to be in solid regular therapy. I had to slowly but surely reorient my focus to my own health.

I also read lots of books on relationships and communication from the library. I also read up on my own mental health issues that were related - such as having ptsd and also being the adult child of an alcoholic.

I wish you well, I sure feel for you, I remember experiencing that kind of pain. Somehow therapy, time, educating myself on mental health and relationship issues, and developing a focus on fun hobbies all helped me.