I just wanted to share an excellent book that my therapist recommended to me. I've read most of it and it is very helpful. It is all about setting boundaries in various relationships. It has good tips about how to deal with difficult people/situations. I have personally used some of the techniques with my mom who is very toxic, and they have worked. It also has some material about dealing with people who try to badger you about religion.
The title is "Where to Draw the Line-How to Set Up Healthy Boundaries Every Day" by Anne Katherine. Here's a link: