Starsky~ I would never lie either, but you can say a lot without lying.
You're all splitting hairs. You can't say "Don't expose," and also "But don't lie if asked." That turns into a silly game of "Hey, if you ask me the right question, I'll tell you the truth!"
Deceit isn't the kind of foundation on which to build a family. My wife and I teach our kids that no matter what happens in our family, we will ALWAYS tell each other the truth.
And as for the OP's spouse, why should they be the only one of the four to NOT know the truth?
That's pretty disturbing news I keep hearing about people getting BANNED from this forum for speaking the truth. Maybe I signed up for the wrong forum.