In my early-mid twenties I was doing the 50+ hours a week thing at my gig for almost two years nonstop chasing a bag.
Someone quit, and rather than hire another person I said I'd make up the slack working OT since I had just had a kid.
Like overtime every day, and coming in on saturdays or sundays when I could drag myself out the crib.
Near the end I started cracking mentally, and then my hair started falling out in patches from the stress. Eventually I had to sit down w my boss and ask her to hire another person to help me. She was willing to keep paying me the overtime indefinitely, but it was KILLING me, seriously.
I honestly get angry at myself when I realize how I blew through so much $$ without putting a lot of it towards something more long term.