When ManFriend passed away, I was left with the feeling that I didn't know if he appreciated our friendship / cared about me like I did him. I was hurt and angry that he died and I didn't get to say goodbye. But I realized in his way, he did reach out to me, he called me right after he got the news and he saw me twice. Even though he lied to me, he did what he needed to do so he could die knowing he saw me and talked to me and told me how much he valued our relationship at the time.
I think it is important to tell people that, and while moving is not the same as dying - I felt like I needed to tell my friends how thankful I was for our friendship, and realistically I know I won't see many of them ever again. I had thank you cards made up notifying them of my move and thanking them for all their support, love and friendship over the years. Aside from the words I had on the card (front or inside) I added personal messages to everyone. Writing many of the cards resulted in teary eyes as I thought about all the great memories they've given me.