Hardly insulting, is it? I might just not be woke enough. “My wife” sounds a bit possessive and subordinating, although it isn’t. “The woman whose husband I am”?
Not everybody is married anyway. Not all are male, and/or partnered with a woman of course. I’ve never really liked “my partner” because of its business connotation, and “my life partner” sounds a bit pomposo.
The possibilities for giving, or taking, offence are endless.
I variously refer to a certain person as “herself”, “the boss”, or “my boon companion”. Is that bad?
Most of these drolleries are harmless, they come and go. Remember “her indoors”? I probably wouldn’t use it myself, although I doubt if the boss would be put out if I did.
EDIT: I have just enquired of my boon companion whether she thinks SWMBO is offensive or not. She said “No”. When pressed as to what she did think, she said it was probably a term of endearment. So there we are. And she’s a member of the provisional wing of the WI.