You could try sam-e if you are in a country that isn’t prescription only (many don’t require one).

Imo meds alone won’t do a ton of good, if you’re battling depression or constant blahness you should also be trying to steadily make improvements in your habits and life situation. When you are not feeling too down try to make a list of things that might make daily life more pleasant and try to work some of that stuff into life. Things like sitting in the sun or watching the sky aren’t too trivial. If nothing sounds pleasant (because depression) imo you have to go the regimented route where you add things to your life that you think would improve anyone’s situation like eating healthy, exercising regularly, and picking up a new hobby.