I totally meant 4 noble truths. typo, oops.
Anyway, if it's all too long, and you didn't read... Long story short you are miserable because you want shit that you can't have, and you let it effect your mood.
By "shit", that can be anything. It could be material, sensual, or even emotional.
As long as you are thinking about not being depressed, you are going to be depressed. You just have to let the thoughts kind of fly past you. That is what meditation attempts to teach.
Just some help from the most Cosmic of all Alfonzos