ReindeerThistle
Zimmerwald Left
I have been feeling sad lately
And as you said, it will pass. Moods come and go, and they are just moods. You are a scientist, I find comfort in the words of Democritis, father of modern science:
"Opinion says hot and cold, but the reality is atoms and empty space."
Cheer up. I had a friend (may he rest in peace) who said "If you are in a situation and at least one of your options is living, you DO NOT have a problem."
He was in the same line of work as I am, and spent much more time in jail.