Wet, sounds like you are a more forgiving person than I. I probably would have told her that hypocritical people who want to do illegal gun purchases do not stay in my home. At which point I would have referred her and her husband to the farthest 2 star hotel I could think of.
End of discussion.
I know that's not really a great way to change someone's mind regarding guns. I don't trust gun grabbers who want to illegally buy them enough to stay in my home with my family.