This morning I told my W. "I know this as much of an uncomfortable topic for you as it is for me but in the very near future, we are going to have to have a conversation about our future. My shift assignment will be changing in a few months and depending on what we decide, will determine what assignment I will decide to put in for."
This is where the "Nice Guy" or "Bad Boy" question came from.
The Nice Guy: "Wife, what should we do?" The bad boy: "Wife, I decided to accept XYZ position"
So if you were always the nice guy with Wife, 180 would be Bad Boy attributes.
For me, I was certainly always a "Nice Guy" before. i certainly dont have that "Bad Boy" attitude. But Im much closer to the middle now.
So, based on your example, I would sit down with W and say something like "As you may know, my assignment is up at XXX. Im interested in pursuing an assignment that does YYY and ZZZ. Do you have any thoughts?"
I feel like as your W, she should be involved to some degree. But it is your career and you should have ownership. So figure out your best case scenario and propose that as a starting point. It isnt a joint decision....it's your decision to which you will listen to her input.