"At such moments I don't think about all the misery, but about the beauty that still remains. This is where Mother and I differ greatly. Her advice in the face of melancholy is: 'Think about all the suffering in the world and be thankful you're not part of it.' My advice is: 'Go outside, to the country, enjoy the sun and all nature has to offer. Go outside and try to recapture the happiness within yourself; think of all the beauty in yourself and in everything around you and be happy.'
I don't think Mother's advice can be right, because what are you supposed to do if you become part of the suffering? You'd be completely lost. On the contrary, beauty remains, even in misfortune. If you just look for it, you discover more and more happiness and regain your balance. A person who's happy will make others happy; a person who has courage and faith will never die in misery!"
-- Anne Frank, The Diary of Anne Frank, March 6, 1944
I read this quote a couple of months ago at Gretchen Rubin's Happiness Project blog, and it keeps coming back to me.