Life is but a vapor

Today i found out that a classmate from grade school passed away--yet even worse, he was mugged, and now gone. words cannot express the heaviness on my heart, but some of the thoughts i have had are in relation to how quickly we come and go. how short life really is.....it's so sad that i have days where all i can do is whine and complain.....Lord teach me to number my days!
help me to be so thankful to be alive and to live each day to the fullest!