Just my 2 cents....but sometimes friendship just changes and is not what is was at an earlier time. Circumstances in ones lives change and our priorities are not what they once were. This is not necessarily a bad thing, just part of Life.
Remember the good times and learn from the relationship that you once had. In my opinion, a relationship that requires excessive strain, toil and worry is not a mutually healthy relationship. Real friends can be honest, understanding and considerate just because that's what they do...no effort or work.
Now, don't get me wrong I have some life long friends that I may not see nearly as often as I'd like, but they have always been the same kind of person year after year. I can pick up the phone and be right back to wherever we left off the last time. I also have a few folks that I once considered "friends", but over the years I have realized they were just passing through my life, not really staying forever. They added to my life at the time (hopefully I added something good to theirs, too), but in the end I probably wouldn't count them among my true "FRIENDS".
Maybe that would be a good thread .... "FRIENDS FOR LIFE?"
Now, for my advice....just do what you are totally comfortable with, but remember you can't make a person conform to your requirements. My mom's best advise has always been, "Just do the right thing and be nice."