I suspect she will come around in time.
She has shown a propensity to 'jump over the Watchtower fences' before. She has most likely been 'counselled' about association with you. She is terrified that if she goes to far they will know somehow [God's Holy SPirit?] and she will find herself a disfellowshipped elderly lady with no one to turn to.
I hate to say it; but this happens all the time unfortunately.
If you still believe in God pray for her, if not do all you can to maintain decorum that will attract and not repel her further till she comes around.
Good Luck
Jeff