The only constant thing in life is change. We've heard that simple truth for umpteenth times, but more often that not, change still takes us by surprise.
A colleague of mine just resigned today. He is the first person to resign after more than two years; hence it's like a wake up call for everyone that in this life, people come and go. Very few people stay and become a permanent fixtures in our lives. And if the time comes for them to go, you cannot hold on to them. You may want things to never change, but life is not like that, whether you like it or not. Therefore, if you have friends who have been with you since kindergarten, or even high school, and still remain close after all these years, consider yourself lucky. Very lucky indeed.