When I'm having a particularly surly day my best weapon is gratitude. While I'm whining about the extra 10 pounds I gained over the holidays, or that I don't have the money to go to India over the summer, there are people with real woes, like say, not having food to eat.
It's a depressing thought, I know, but by turning it around it can actually create a better state of mind. If you stop to look for a minute you will find a lot of things to be grateful for. Even the simple things like a piping hot shower in the morning, choices galore on what to eat, books to read, and let's not forget being grateful for good health.
One of my favorite sayings on the tag of Yogi Bedtime tea is, "To sleep, don't count sheep, count blessings then sheep." Even if you're not the praying type, it is a good practice to count your blessings and be grateful at least once a day. Try it, you might like it.
As for those folks that don't have as much as we do - Feeling bad about it does't help them. What does? Feeling good and grateful so you can make a positive contribution in the world.