Yes, we've never really had this discussion, at least in part because I was afraid that it could result in some kind of ultimatum, or an attempt to take some territory back. "Either you go to a urologist, or to counselling, or we go to a lawyer..." kind of thing. Or, "You can wear them at night, and if you want to dress like a toddler when you go out with your friends, I don't care, but when we're together, my expectations are that..."
So her saying, "Well, I guess you're ruined yourself in that regard, haven't you? We'll just have to work around it, but I really wish you hadn't..." is really one of the best possible outcomes. I suppose if I were writing an ABDL fiction piece, it might then progress to "And from now on, I'll be choosing your diapers, Mommy knows best..." But that's probably not what I want, and it's definitely not what she wants. The power dynamics in our relationship are pretty complex - she is a dominant personality, but at the same time, I've been the financial prime mover for our entire lives. I don't lord that over anyone - raising kids is arguably as, or more important than the age of your cars and how much space is under your roof, and I am the first to concede that I have never shopped for bras, or fitted dance costumes. But, there are hills I am willing to die on, and she has eyed them enviously, but knows not to mount an assault.
Meanwhile, this morning, I ambled down to the kitchen, after sleeping in longer than I had intended, in a robe, and a soggy Active Air under plastic pants. She heard me coming down the stairs, and made me a coffee, and then we sat and chatted and doom-scrolled current events on our phones. I'll enjoy this morning of relative diaper freedom, before my in-laws arrive this afternoon. Even if I have an inkling that they, or at least my mother-in-law, know something, that does not put me in a position where I can live like it's just my immediate family in the house with me. I'll wear decent diapers, but I'll be changing them a bit more often, and whereas I might prefer, under certain circumstances, to be in, say, track pants, I'll stick with jeans later into the evening, because of their better camouflage characteristics over bulky nappies.
I will not give up sleeping in just a diaper, however - I am going to ask my wife to please default to leaving the door closed, if I'm in a state of undress, and she's coming in and out of our bedroom. My mother-in-law haunts my upper hallway like a specter, silently gliding back and forth in unpredictable ways, at unpredictable times. I don't want to wake up, splayed out on my bed in some absurd, mermaid-themed ABDL flourish, to her silent presence.