I know i'm being a bit unorthodox here, but also consider doing some drugs. DONT use them recreationally and also only use the right ones. An LSA or LSD trip spent examining your spirit and mind can give you a lot of insight about life and a better appreciation for it. Also, dont be scared of a "bad" trip. There is no such thing as a "bad" trip, because you need to experience that to truly appreciate the good trip and the goodness of life in general.
And if you want to go all out, go to south america and spend a month with a shaman doing ayahuasca. I've heard of people getting off of 20 years of depression after 1 trip.