My Parents were pissed when I didn't get baptized forty years ago. They get over it. Being an unbaptized born in is a helluva lot better than being DA or DF. Never answer her questions unless she has asked you one you want. She is the one who is preaching that she has the way to your salvation, so make her answer your question and make her feel guilty for every tactic she ever uses to weasel her way out of answering your question. If you can make it only one very important question and insist on her, (not an Elder, it must be her) answering that question, honestly, you might be able to tame the beast. It worked for me. Ask a question that sends her off to find an official answer that has never been honestly addressed by the WT and never let her change the subject by any means. The more she wants to avoid that question, the more insistent you should be that it should be answered. She has to feel guilt for avoiding the question, trying to bully you, lying, using double standards, whatever tricks she uses. She has to know that you have higher standards than her. She has to know that you do not feel guilty for not being bullied into joining a church of her choice, especially if she won't honestly discuss it's doctrines/failings/whatever. I didn't say it would be easy.