Hello SteviePDX: Another mom of an AS here. Some years back I told my son he was no longer welcome in my home or in my life until he addressed his root problem. Other than that, I had nothing to offer him. But if he were to choose to get help, I would support him in any way I could.
For several years after that, he would answer the phone whenever I called and would occasionally call me just to touch base and say hello. Sometimes I would meet him and buy him lunch. But in the last year - nothing. He is very angry at me, very hurt, and that much deeper into the problems associated with his drug/alcohol use.
So what I do now is I will once in a while (every couple of months) put a message on his phone just saying I love him and miss him. That's it. If I have his address, I might say that in a card. That's it. I had talked to a counselor (a recovering addict) who encouraged me that my son still needs very much right now to know that he is loved, especially by me, his mom. My son never responds to these messages, but I still feel better having done it. And I am hopeful that those messages go to a place in my son's soul that addiction cannot touch.
Just my way of dealing with it. Hope that helps.