I was supposed to go on some pills Im not to sure as of yet because i am under 18 [I am 15]. So I go to counselling when its really bad, or write poetry and song lyrics.
when my horse had died from a disease [3 weeks ago] and my parents split up. I had written 15 poems and seen the couseller 3 times in a week.. but all and all it was really helpfull.
as for what triggers it.. it can be anything
my grades, looks, going around sharp corners, losing friends and pressure is a lot of it.