Thanks for your thoughtful reply and for asking me those questions.
She did continue to pat my butt well into my teenage years, in spite of my protests.
Matter of fact, she did it again probably about 8 or 9 years ago, when I was 33 / 34. It was highly inappropriate, and I told her to STOP TOUCHING ME THERE!
It was only in the last few days that I came to see that she has probably been sexually attracted to me. It's disgusting and repulsive. And yet I can't blame her, she's also the victim of incest.