Sadly, it's going to happen on both sides, RFMO. I remember when I was leaving I had a friend complain mightily. She said she always assumed I would be there for her, and that I would not actually get the visa and leave her. I said, very gently, that I wasn't leaving her, I was going home to my husband, this was not about her, it was about me and my husband. It was not an easy conversation for me to have with her, we have been close for years. She even tried lamenting to my husband that he came and took her friend her away, emotionally and then physically.
Our friends do not always accept our choices. Good friends will eventually come around and accept the new dynamic of your relationship. Seasonal friends and friends who were only around for what they needed from you will sooner or later drift away. Don't try to hold on to them, instead expand your circle of friends and make new ones, grow into people who are walking the same path you are, can empathise with your feelings, and that you can give more to based on who you are now, not what you used to be.