Wow, Mary! That is just crazy! I really admire you for having the fortitude to rise above what that woman is doing. Here I am going crazy over just two little ring designs. I don't know what I would do if someone was stalking my shop!
I know that some of the TYPES of rings I make are not original, but those that aren't, like the stacking rings, I try to put an original twist on them. And some of my rings have definitely not been done by anyone else on Etsy (or anywhere else that I can find, for that matter). And if someone questions my originality, well, they're not looking close enough at my items.
I just have to ignore those people who are potentially hurtful and, again, let karma take its own sweet course.