Tell her a little story.
You can lead a horse to water, but you can't make him drink. If you presist in trying to make him drink, he will eventually become annoyed, and kick you. This will hurt, probably quite a lot, and for quite a while. I prefer not to be kicked by the horse, so if he refuses the drink when I show him the water, I will tell him, "this is where the water is, and if you become thirsty, return here to drink." I will then have done all that is possible for me to do, and will feel no remorse should the horse die of thirst.
"Mit der Dummheit kämpfen Götter selbst vergebens."
("Against stupidity, the gods themselves contend in vain.")
-- Friedrich Schiller (1759–1805)
Reality is that which, when you stop believing in it, doesn't go away.
-- Philip K Dick
OK, now let's look at four dimensions on the blackboard.
-- Dr. Joy
English isn't much of a language for swearing. When I studied Ancient Greek I was delighted to discover a single word - Rhaphanidosthai - which translates roughly as "Be thou thrust up the fundament with a radish for adultery."