I used to be a little obsessed over the concept of friendship, to the extent where I would wonder why some friends had to depart from our lives at certain points in time. I would begin doubting the "true" meaning of friendship. And that was until I learned that impermanence and change is one of the basic facts of existence.
Right now I no longer would deliberately label if someone is just a normal friend or a really good friend. A friendship is best left undefined sometimes because we will never know what is going to happen next, and we don't want to end up getting hurt by the boundaries and expectations we define for ourselves and friends. Over time we will eventually be able to tell the depth of a friendship.
Regardless of what is going to happen, I have learned to appreciate better the bond of being together with all the friends who come into my life. I have come to slowly appreciate the "nowness" of each moment, because I know it isn't going to be forever. One day there may come a point when we have to move on and say goodbye to some of our friends too - we just never know.
But that is okay. I guess when the time is right again, re-entering each other's lives is never an uncommon thing. And in the end, will realize that some of friends have never really left. Why, they've always been there! It's just that they are occupied with something else as they move from one chapter to another in their lives, just like how I'm doing exactly the same.
Just want to say it's great to have you in my life. The experience with each of you has been very different, but that's only because everyone has their very unique personalities that cannot ever be replicated. :)