I am the pot calling the kettle black here as when I was a super and then an APM I would often average about 50-70 hours a week depending on if I worked a weekend or not. I stepped away from the industry about a year and a half ago but many of my friends and family are still in it and I also sell to the industry so I am still in touch with how things are.
I know things are always dependent on the project/management that you have but I have come across so many people who simply do what they can on a daily basis and then walk away for the day. I know of PM's that were starting their days at 8-9am in the morning and then were gone at 5pm.
I am considering going back into the industry and my biggest thing is avoiding getting burnt out again. I put a lot of the pressure on myself to succeed/worked longer hours at times so I feel just simply accepting that I am going to do what I can in 8-10 hours (or 12 depending on the day) and then calling it quits is the best solution for when I potentially return to the industry. I was always a top performer and was on top of my trades while I was at work so ultimately I know I am above my peers typically and in todays market companies are doing whatever they can to retain good talent.
Is the key to just simply care less, do what you can, and ultimately see that at the end of the day it is just a job. We work to live not live to work?