You might try pouring some of your e
juice on your hand while she watches, letting it sit there for a bit in front of her.. do a small demonstration of there being no burns, and no death associated with your e
juice getting on your hand..
Then, hand her the print out from the royal college of physicians on the safety of ecigarette usage as compared to smoking..
Then, just walk away.. there is nothing more for you to say, nor argue about. She saw live and in person the fact she was lied to, and you handed her proof from actual physicians that she is being lied to, which she can peruse at her leisure.
That's it, nothing more for you to do or say.