Until now, no one can give an exact answer to the question you have raised. I have seen this questions in the general board before and people keep beating around the bush without spilling it out. To my own understanding, no matter how you value your privacy, there must be someone to know about your secret seed phrase or how to get them when you’re no more. I see no reason keeping it hidden from the whole world, then leaving it behind as waste without anyone getting to use the wealth you’ve accumulated all this years.
Not every marriage ends well although marriage should be built on trust but not every marriage can do this, so it's safe and it's not at the same time, if you feel you and your wife already buildt this mutual trust to the extent of your bank acccounts and it's being going fine for years then why not, but that's incase of emmergency though..
For me, there's no reason keeping that you're into bitcoin or crypto in general but that should stay only with your families , keep it hidden to the rest of the world.. and for the access to you wallet, that should still stay hidden to only you unless you build a muttual trust in your patner already but imo with that i will stilll prefer to keep it hidden.