At spare moments in the day, make it a point to contemplate the loss of whatever you value in life. Engaging in such contemplation can produce a dramatic transformation in your outlook on life. It can make you realize, if only for a time, how lucky you are - how much you have to be thankful for, almost regardless of your circumstances.
"A Guide to the Good Life: The Ancient Art of Stoic Joy". Book by William Braxton Irvine, October 7, 2008.