what are friends for?

Friends are an interesting thing. We find people that fill some need within all of us. Someone to participate in activities with, share common feelings or experiences, potential loves, or just someone to spend time with. What really makes friends interesting is when things start to change. When what was once a shared need changes for one person. One of the friends has the need satisfied. The unsatisfied friend is now left going to this person to share or partake in what is no longer a mutual relationship.

I guess a true friendship would be able to address this situation, work through it, find some other common ground or experience. But what about when that doesn't happen. When people start to drift apart but don't work to or can't find something to retain their commonality, but they still hang onto each other.

I think all of us have probably been there. That friendship that just seems like its more work to be friends than to just let go. Where you struggle to find some common ground, but find mostly silence and awkwardness filled with empty boring attempts to talk about stuff that neither of you care about. Is it worse to just let go? Or keep looking for that one crack of interest that both of you share and base a whole relationship on it?