I believe it is all in the way you think.
What "Pirate's Quest" said is very true. There are people less fortunate than you and thinking of this would remind you of how grateful you should be for what you have.
Remind yourself of all the wonderful things that you have. Even the pen you have to write with is something a lot of others cannot even afford. We take a lot of things for granted.
Smile.
I hope you begin to feel better!