maybe we should take a step back and ask if you agree that a married couple should have their own personal bank accounts and maybe a joint savings account and another joint account where they pay the bills out of. i doubt spouses are going to be checking the other's bank account statements each month anyway so as far as that goes, it effectively is a bank account they know nothing about....
Many couples have separate bank accounts, but they at least tell or are open to their partner about it. Having a secret bank account is another story, I haven't heard that too often. If you don't want to share everything with your partner you probably shouldn't get married in the first place, since you're legally accepting that you will share everything.
I'm not even sure what the motives would be to hide a bank account from your partner. What does that achieve?