The term "depression" is a misnomer. Something like "obliteration" would probably be more apt to convey the experience of having the disease.
In this inspiring lecture by Robert Sapolsky, we find out that depression has it's roots in our DNA. In other words, solving depression isn't about sucking it up and bearing with the pain. I'd encourage anyone to watch the talk in full (53mins) for a great, yet entertaining, perspective.
For those who are blessed with the genetic makeup to have avoided this crushing ailment (myself included), the least we can do is see it for what it is, and respect it for that.
Send the PDF to the Naysayers.