If the relationship with your own wife is not very prosperous, then the private key should be kept secret even from her. Otherwise, at some tense moment of your married life, she will transfer your joint bitcoins to her personal address, to which you will no longer have a private key.

But this is fraught with the fact that quarrels can occur in families because of this. Because the one who owns the private key also owns this money.

On the other hand, if you bought these bitcoins with your joint money, this means that both of you will need to know the private key to the address where they are located. A certain dilemma arises in this case.