it can be that its entirely chemical, cycling back again and again. sometimes thats the only explanation when you worked thru your stuff. i reached that point with my depressions, they were suicidal and it wasnt over anything other than i kept getting depressed over nothing, it was tiring. exhausting more like it. i didnt like the idea, but i knew i would end up dead if i didnt, so i finally started taking meds and the depressions been gone for a few years now. i stopped taking them last october and so far so good. hang in there.