A strong desire to continue living in Japan, where this is pretty much the societal expectation for professional work. I stayed there three years because I had made a commitment to do so to my bosses. They had staked their careers on "This wild unprecedented decision to hire an American will not blow up in our faces." They were scrupulously fair in their dealings with me, particularly in one way which is table stakes in the US but requires anomalously strong moral character to do in Japan, and so I tried to uphold my end of the bargain.
It seems like they killed you with kindness. My grandma likes to play the saint and guilt me into doing her bidding to this day, I've become allergic to this.
With such a crazy work schedule, does that even allow you to enjoy the reasons/desire to live in Japan? I mean, how much time is left in a week to live your non-working life?
I am assuming here that these was when you were single..