Honestly, people have different perspectives and wants and needs when it comes to friends. I am very close to friends but the way we hang out and where we hang out is very fluid. It has to be as we are "just" friends. People come and go and we stay in touch
I live in a town where, as people here have seen, I go to 15 to 20 going away parties a year. It is a transient town and this is something I have grown used to. Friendships outside of this bubble are no different, albeit the rotation moves slower. Its natural imo.
As for your "needy" friend. There are lots of people like that, some people just can't be helpful to others as their problems encompass their entire lives. They see everything else as less meaningful than their problems. I have never found a way to deal with these friends beyond
a) stick with them and keep playing the role they need
b) drop them like a rock because it is a one sided selfish relationship
I am a sucker for helping people, so its usually (a) for me...