My mom (who I live across the country from) recently went through a terrible bout of shingles, and had a lot of trouble with the pain. She was prescribed several different pain meds until she found one that really worked for her - unfortunately the side effects were really intense (confusion, brain fog, forgetfulness). She seemed like she was drunk all the time on them, and wouldn't remember things from one day to the next. I expressed my concern about her safety while she was taking them and said I didn't think she should be driving while she was taking them. I also cited a few examples of memory loss and out of character behavior that deeply concerned me, and asked her to connect with her GP or pharmacist to talk about the pills. She has a lifelong tendency to only hear the negative, so I knew she wouldn’t hear my concern and only take it as criticism, but I had to say something. But as I should have predicted, she got so upset that now she's not speaking to me. My husband tried calling her to talk about it but she froze him out too.
Rereading my favorite family dynamics book Adult Children of Emotionally Immature Parents. But would love any other words of wisdom.
Also come to eventually figure out that the reason she was overdosing herself was that 1) she was a total baby when it comes to pain; and 2) she was at the beginning of her short-term memory loss. She eventually was moved into AL because she could no longer take care of herself (and her husband was given a legal guardian and moved into a facility due to his advanced Parkinsons).
You will need to make the decision of whether you wish to be your Mom's manager or not. It won't be easy from so far away PLUS her being uncooperative, but it can be possible. As long as you understand the time, money and emotional commitment it will require from you. If you are not now her PoA, then it will be even more difficult. Even with PoA it is difficult to get an uncooperative adult to do something they are physically resisting.
You don't mention how old your Mom is or anything about cognitive impairment. If your Mom is now old enough to have the beginnings of dementia, then the book I would be reading should be on that topic, since dementia breaks a person's brain is such a way that the prior rules of engagement may no longer apply.
I wish you much clarity and wisdom as you ponder your next move.
Stop contacting her.
She is an adult and has made her own choice.
She is not your responsibility.
Send her a lovely note with ZERO discussion of all of this. Something short and sweet. Beautiful card saying:
"Dear Mom:
It's my understanding that currently you wish to be out of contact with us. That's fine if it is what you want. Know we love you and are here if you wish to make contact again".
Stop allowing her to "play you" because you aren't a fiddle.
Stop allowing her manipulation.
Make her responsible for her actions and get on with your own life, giving her as little thought as she deserves.
Just my humble opinion. But you're an adult as well, so I leave your own choices for your own life up to you.
Good luck to you.