My daughters have gone through just what you are experiencing when they visit my parents. My dad can't talk about anything but his JW activities. If he does talk about anything else, it's to criticize worldly people. He's gotten a little more bold about his displeasure of a college education and unfortunately has alienated his oldest granddaughter (who has since finished her 4-yr college degree). The youngest will be visiting right before Thanksgiving. She is a senior at a 4-yr college and has plans to go on to a PhD/MD program. It is so difficult to put up with their subtle propaganda but the girls love g'ma so much and can't imagine sawing her off just because they disagree with JW teachings, especially since g'ma is up in years and won't be around for too much longer (she's 81).
You mention writing a book - try journaling, even if you don't plan to publish. Write your thoughts and feelings down. It might help you sort out the emotional stress and get it out of your head. Just a thought. - Mrs Rocky