First off.. I hope this is allowed!
I've literally just published a book on overcoming depression, called 101 Distractions from Depression, Self-harm (and other Soul-destroyers) It's an eBook available on all Amazon Kindle stores (that's the link to the UK store, but you should be able to find it on the others too).
I suffered from depression for over 10 years, and I know how horribly crippling it can be. The idea behind each of the 101 distractions is exactly what others have already stated - its about taking your mind off things to allow you a bit of 'breathing space', which helps you appreciate that depression IS NOT permanent.
Anyway.. I could talk for hours on this so I won't bore you all. I just thought it was worth me mentioning the book because hopefully it can really help some of you.
If you'd like a bit more info, have a look at www.distractionsfromdepression.com
*big hugs*