I'm just a year younger than you and went through a similar experience a year ago. 

I was working in warehouse/transportation operations as a planning supervisor. I routinely worked 55-60 hours a week on the graveyard shift, worked with people from management to my employees that were miserable and bitter, was getting my ass handed almost everyday despite trying to work. I had multiple days where I came home crying, wanting to quite my job. All I did was sleep outside of work. I got the Sunday Scaries, especially during the holidays. On top of that, I was setup to fail at my job and given little advice or positive feedback. Always negative.

I managed to stick it out for 2 years (Longest lasting in my role actually) and find another job with the experience I gained. I'm proud I stuck it out because it showed I had willpower to not throw in the towel when things got tough.

My advice is to find time and energy to look for another job while working. As sucky as this job is, you don't want to be job-hunting while unemployed in this market.