Craig it started when Chris Tuckner was talking to me about his 2nd wife if I recall. It could have been his 3rd, I really don’t remember.
I started using “my 1st wife” when talking about Deb, my one and only. I thought that might lead people (like my FW) to think there’s going to be more, so I changed it to Favorite Wife. After a short while it was shortened up to FW. FD= Favorite Daughter FGD= Favorite Grand Daughter and lastly FM= Favorite Mom.
You make take the liberty to make the FW anything you like…although if you’re going to use the one you like you might want to keep that to yourself when your FW is around.