I know you might think suggesting meditation or eastern philosophy would seem dismissive or unhelpful. But its what cured my depression. Consider the yogi ascetics who live in the slums of India who sit on beds of nails all day, they seem happier than many Westerners. They have a understanding of human consciousness that many modern doctors in the West lack. I recommend reading the Vedic Unpanishads, its not that long and you will find that it makes perfect sense despite being written a thousand years ago. If you're not interested in that I suggest you try learning how to lucid dream and astral project. If you practice the skills from the Vedic texts those skills will come naturally. I've had experiences in the dream/astral world that really brought me out of the depressed state of mind and re ignited my sense of wonder and mystery.