Hi "John",
Welcome to the forum! I don't know, maybe you have probably done this already, but when she calls you say your name to her, as a reminder, sorry if I sound sarcastic but maybe it will eventually sink in. Are you sure you two are really getting along okay?? Even when I am not with my husband, I still call him by his name, it is just natural. What is weird when my mom speaks to me about my dad she'll refer to him as her husband instead of "your dad" but than other times she say " daddy" says hi, blah blah. . . I guess it depends how annoyed she is with him on that given day, they are retired and an always bickering about something. We are going on 25yrs of marriage next April, you wonder where the years have gone. I don't know what more to say, I don't know what your wife's problem is, did her mom treat her dad like that when she was growing up? Try to have a "calm" talk with her again, let her know how hurtful this is, gosh I even call my dog by her name all the time Good luck and take care now.
"darkeyes"