I've been trying to explain depression to certain people in my life for years. It's not that I have anything to be depressed about or that I'm dissatisfied with life. I don't "just need to think positive" or "have faith". Believe me, if it were that easy, I'd have done it a long time ago. Rather than trying to go into the details again, here's a great comic that explains it much better than I can.
http://www.buzzfeed.com/hnigatu/comics-that-capture-the-frustrations-of-depression
Here's another comic about depression, this time in the form of a personal narrative. There's a little bit of bad language, but it's done in a relevant way; sometimes those are the only words that work.
http://hyperboleandahalf.blogspot.com/2013/05/depression-part-two.html
I can relate to feeling nothing.
Hopefully these comics have been helpful to you; sometimes just knowing that someone *understands* makes a big difference.
