AA brought me back from a similar place. Prayer does help too. Hand your life over to god and let him do the worrying, what have you to lose if you feel you have nothing? But you have, you have a life, look around you, I mean really look, not at things, your possessions, people, but at the gift of nature - look at the trees, a lake, the sea, mountains. Keep on looking for sadness and you'll find it, look for happiness and you'll find that too.