My grandfather, then a pre-teen, walked a 10 mile trap line each day in Nebraska winters during the great depression with a rifle and collected various small animals that were brought back and eaten so his family would be less hungry. In his mid to late 20s, he received three wounds and a bucket of awards for his actions in Guadalcanal and Burma. His wife to be's family got by by making illegal moonshine and hiding from the feds in Oklahoma.
The most important lesson he taught me was simple, and I've never forgotten it.
Every day you're breathing is a good day.
I understand the limitations of this statement; clinical depression is a real thing, and is, fortunately, largely treatable. And situational depression can be pretty brutal.
You are alive. You are breathing. You don't know how many days you have left in your life. Most likely you have a lot.
More importantly, you have little idea of what those days will bring you.
I've been living in a lot of climate change related fear for decades now. 20 years ago, the science was just getting started, and nobody really understood most of the implications.
The fact is, we are all pretty helpless about most everything. That you're here on Hacker News is an incredible twist of fate, rather than starving in a refugee camp somewhere.
So, assuming you are not clinically depressed, I will say this: live today and rejoice in its wonder.
If you are alive tomorrow, live it, and rejoice again.
If it is our fate to succumb to the https://en.wikipedia.org/wiki/Great_Filter then so be it.
We live in fantastic, interesting times. Enjoy the ride and do the best you can to fractionally move the various needles in good directions.