If we are fortunate with our friendships we encourage ourselves and others to adapt to the life changes that are taking place within ourselves and others.  Much of our emotional life is finding healthy ways to handle the frequent changes that we and others make with our daily choices. 

Making healthy changes in self tends to be one of the most difficult challenges we humans have.   Some may choose to change their friends or seek new friends as our life path varies.    We can build historical friends of many years if we accept that "we do not have to change friends when we accept that our current friends are also changing - just like us."