I don't know if it "depression" in the clinical sense of the word but I sure feel a deep emptiness and sadness after AVATAR which so clearly reminds me of the outrages others of our species( and the governments that allow it) continues to inflict on our Earth and the animals, birds, fish and other creatures and plants that live here, whether it is another mass cutting of a forest near my home or in Brazil , the foul death machines they call commercial fishing boat, etc. etc.. Oh that we could treasure the wonder of Creation as the Na'vi rather destroy it. Seeing that in the film and then getting back to our reality can be rough. Pandora is not real,but how I wish it was.