Sleep, eat 'happy foods', get out into nature, exercise, have a good scream, find someone worse off then you are and help them.
Or lay out under the stars, with good company if possible, and contemplate that there are something like 200 billion galaxies and millions of stars in each. We are pretty much insignificant in the scale of things. If we parlay our knowledge base into becoming a great space-faring species, or die in a whimper of collective bigotry and incompetence, the universe will not blink. I find that very comforting.