Even though my manager knows my JW history and how I'm being shunned, he still does not seem to appreciate what I'm capable of sacrificing in order to preserve my mental wellbeing.
Straight up tell him, then. "Boss, you know how I have lost so much. I will do XYZ and sacrifice everything in order to preserve my mental well-being. I know I am important at work and you know I need my time away from work. I am sure we can work out something better than my being figuratively at work 24/7."
Just my opinion: If you are not ready to tell him your answer, then you are not ready to sacrifice it all. If you are ready to sacrifice it all and still won't tell him, then you won't be happy there and want to leave.