I'm so sorry this happened to you

May I suggest going to the Association and asking them to speak to her and explain there are laws against discussing someone else's private medical situations. Also, I would take it upon myself to tell her in no uncertain terms that your private life is just that PRIVATE.

The next time I was in that situation I would look at her very coily and say "Why, I have absolutely no idea what you are talking about.". Then turn around and ignore her.

Hugsssss
J