I can well understand your feelings, it is unfair what life hands out, both legally and physically. I'd be the last person to suggest you do not continue with your efforts on both fronts, to get medical certainty and a satisfactory settlement.
These however is things that can take all your mind all the time. I had an anomaly on a lung which convinced me I was heading upstairs, and I've had legal proceedings which have had potentially rather serious consequences. Both have made my life miserable at the time.
I have found however that having one thing one enjoys to look forward to each day makes a big long lasting difference. It might be several chapters in a book, a favorite movie, other things like that, plus talking to someone I care about.
True it does not fix the problems, but puts one in a better mental state to cope.
May I ask what sort of things you can think of to use?