I struggle with that too and what I try to think is, true friends are hard to come by and true friends stick close by good and bad, others will pass with time, but the true ones are there in the end.

Hope this helps? I have the same problem right now, but I am trying to not make it all about me, I tend to do that, it is probably something they are dealing with and it may be their issue and not yours,. One thing I have learned lately is we have no control over what other people will feel, think or do, no matter how hard we try, they are entitled to their own opinions, feelings and behavior.