If I tell my wife about an investment, she wants me to sell. If it's up, sell and take a profit (a brother-in-law is doing very well on short term trading). If it's down, sell before you lose more! There's no up side to telling her before the end. Everybody is happiest with the policy of just keep her in the dark (on a few certain subjects) so maybe she's half a mushroom.

And if you tell your wife, then the next day an asteroid destroys Schaft Creek, you have two disappointed people instead of one!

(On the other hand, what's an asteroid made of? I used to read science fiction about mining 'em. We might still have a mine!)