Thank you Chris for the book titles!
Whoever is interested in the shamanic world view: there is plenty of
ways described in how to deal with depression. For the ones with
german language skills, the swizz psychotherapist and shamanic
teacher 'Carlo Zumstein' has much to say about treating depression.
Michael Harner (USA) comes to my mind too ('soul retreavel' for
example, also calledn 'soul hunting').
Sneh