If you wanted you could probably e-mail them and say something along the lines of
Hi -name-,
I know you've been getting quite a few e-mails from me about you joining my fanlistings that you have not joined. I'm not sure what I can do at this point other than if you would let me know that you have no desire to join any of my fanlistings at this time I can delete any future join forms from this e-mail address. Of course, if you decided to join any of them later on you could e-mail me to let me know, and I would make sure you would be added to that fanlisting.
Other than that, there's nothing I can do about you getting the e-mails saying you've joined if it's someone else using your e-mail address. You could set up filters, perhaps, to put all of the e-mails from my address into the trash, or change e-mail addresses, but there is nothing I can personally do.
Sorry about the problems with this!
-your name-
Unless, of course, someone else has any ideas, but I really don't know of anything you can do. If you got her to say that she didn't want to join any of your fanlistings, there shouldn't be an issue with you deleting her when she gets added. Meep, hopefully someone else has an idea for you, but I'm afraid that's all I can think of <3