Burnout

I have a very demanding customer and I’ve worked at some point everyday for the last 4 years. I’ve tried taking vacations often, enjoy hobbies, spend time with friends & family, however I cannot seem to get a real mental break from this. The money is great and hard to leave behind, however this business is absolutely terrible for my mental. My work:life ratio is completely off balance. What are methods or ideologies you’ve explored that have helped you? What can I do to continue this type of work but also improve mental health & relationships with friends and family?