If you have a good current course of intel, that she doesn't know about, I see no reason not to let it play out some more and see where it goes . . . PROVIDED you're willing to move quickly if you need to. It only takes ONE encounter to forever change her (and potentially, your) medical history, and I've seen people ruined financially as well.
Considering your background, I trust you to make a good decision regarding strategic/tactical vs. those I just perceive as waffling out of fear. WHATEVER you do, DON'T, ever, reveal the source(s) of your intel. If she asks you how you know, just say "That's not important," or "I'm not going to tell you that," or -- if need be -- "frankly, I don't think you're in any position to be making demands of me right now."
Maybe monitor the situation, give her a chance to DO THE RIGHT THING, and work on yourself in the meantime???
