I'd first try changing my phone number(s) and see if she gets the message?

I had friends like that when I was young and one of them was found dead (a woman older than I was). Fortunately the other one and she were more buddies than I was with either of them and the other one was a guy so it was easier to break off. The woman was beginning to be a problem, like you say, wanting to hang out more than I wanted to and do things, etc. I was not happy that she died but I have to admit that it was a relief she was "gone".