I have a seasonal depression diagnosis and lifting weights has been by far the best treatment for me. Meditation, light therapy, and vitamins/nootropics are all good on their own, they each sort of take away some of the symptoms, but I wouldn't say the depression isn't still there. But weightlifting is incredible. I feel amazing after a heavy session - deadlifting and benching especially give me a kind of euphoria. Gym fixes my lack of appetite, lack of social energy, disorganization, lack of motivation to work on my hobbies, work focus, anxiety, everything. I can't recommend lifting enough.