Read some of the well researched stuff from jw.facts - all based on Watchtower literature and what it said/says. Use that literature to show her that JW'ism is a false religion.
Sadly it likely will have little effect.
And when she runs screaming from the room because she believes demons have written it and changed the words in the JW literature then you will know once and for all you are on a hiding to nothing.
GET OUT OF DODGE, ROG!