What right do you have to drop such a bombshell on others?
Well depends really, are you a deontologicist or a Utilitarian?
Kant will tell you that telling the truth is a moral imperative regardless of the outcome, indeed, if you don’t tell the wife and something bad happens subsequently because of her ignorance, morally some of the blame for that is yours…On the other hand the Utilitarian will say that your action should serve the greatest good, and sometimes if that is telling a lie, then so be it. The obvious problem for the Utilitarian is of course, who will be the arbiter for the “greater good” and how will you decide which is better…