I'm struggling to find a good work-life balance.  By the time I get home at night I'm too exhausted to interact much with my girlfriend at home
I know where you are coming from. Why do you think you're exhausted?
I work 10 hours a day.  I get up before work to go to the gym, so I'm extra tired by the end of the day.  My job unfortunately doesn't offer flextime
10 hours a day it's a lot. Usually shifts are 8 hours, doesn't your company give you an extra day off work to compensate you for those many hours?
I'm salary, so even though I'm only technically working 40 hours a week, I need more time to get all of my work done.  Since I'm salary, I get no overtime even though I'm putting in an extra 20 hours each week