Abundant sympathies. Personally, I don't touch the long hours at work stuff. You're a corporate lawyer, Cav, why don't you go to work for a corporation rather than the big firm I assume is pressuring you to generate a gazillion billable hours? That was always the conventional wisdom when I went to law school -- you trade off a little bit of income for a regular work schedule by going to work in-house for a corporation.
Seriously, that's no way to live. You're going to ruin your health. Have a watershed moment of some sort. And get some sleep.