I had a boss one time that wanted me to work 50 hours a week. "There's no such thing as a 40 hour a week job anymore" he said. I could get all of my work done in under 20 usually, so doing 40 was bad enough, you want me to put in more time here just so you can prove who's in charge? I didn't work for him very long. There were guys in there that worked for him for years and years, they all looked like husks of men.
If you're not cut out for it don't do it. There are jobs out there that aren't like that, but they're not around every corner. Go try to find one, and don't live a life you don't want because you think you have to.