telling a wife or trusted person some secrets always comes at a risk. by giving them that information they can become a target if someone else thinks or knows they know that information. it's not about whether you trust them but what type of situation it might possibly put them into.
I understand what you are saying but I don't think it makes much difference. If you are rich and someone knows that and uses your wife to get to your money, they aren't going to speculate whether or not she knows something. If she does, great, tell us. If not, call your husband and have him tell us, or else...