My only advice would be: work hard, play hard. It sounds like you've got the work hard part down pat. Take at least a couple weeks off a year. 50 weeks at 12+ hours a day of work is more than 99% of people do. Spend at least 2 weeks at 0 hours a day of work unwinding with your friends on a vacation. Your work will still be there when you get back, and you'll have renewed enthusiasm for it.