well, all I can say is keep trying different juices with her until she says, "Yummmmmm." Also, if you can get her to give it a chance with a cart's worth, maybe it'll be easier on her. There's just no way you're going to convince someone with just one drag, especially when they're not excited about it to begin with. If she's simply not ready to quit, she's not going to.
My husband was bought with $$ dollar signs (as in how much we'd save by vaping) not for health reasons or anything else, so if she's frugal, try that angle. lol He still smokes a few a day but not in the house anymore.