Every one of my friends, including me, has a story about how they used a phrase in conversation that they don't typically say ("Renaissance Faire" in my case, which I have never attended and generally have no interest in), and then seeing an ad for it on either Facebook or Instagram right afterwards. This is purely anecdotal, of course, but it is creepy anyway. The only way to stop this "myth", if it is one, is for Facebook to stop doing whatever it is they do instead of listening to us to get to this unnerving level of targeting.