Thanks, guys. I haven't posted here in a long time because I haven't had these kinds of doubts in a long time.
I know self-pity is tiresome to read about, but since you asked I'm separated from my wife and feeling awkward with family and friends about it so I'm increasingly isolating. I'm working seventy hours seven days a week for what feels like too little remuneration for the effort and it's just an endless cycle, but when I'm not working I just don't know what to do with myself.
I dabbled in AA when I started all this and I found it supportive, but perhaps not the answer for me. But I've been considering a revisit.