OP - have you thought about or tried hormone replacement? One of yours could be totally out of wack. I'm not looking to get personal or for an answer on here, but does it hit your harder when you get close(r) to that time of the month? Maybe it's biological - something to think on. If you haven't done so get your hormone levels checked. ALL of them.

I read a good book (Unmasking Male Depression) talking about male depression and how we (men) go through a 2-3 year cycle because we have so many "outlets" (sports, work, cars, etc) that we never really hit the bottom and come back up. We keep "cheating" the "normal" ups and downs, so we never fully "recover". He get's a little to religious for me, but hindsight being 20/20 I can look back and see 2-3 year "lows" every couple years for the past 20-25yrs. Maybe you're in one of these cycles and can't break out.

I can look back and see periods of time where experience what you fear - not really living interspersed with moments of happiness/joy. Even now and I KNOW better, I catch myself just sitting on the couch watching "nothing" on TV opposed to doing things that need to be done. Part of it is the weather, I live in Texas as well, but even on nice days I don't even feel like riding my Harley. So I understand where you're coming from to a degree.

Find joy where you can and live for the little moments. And hopefully you'll find that thing that helps you get out of bed or off the couch and that makes those moments longer.