Hey CK,
I haven't had to go through this myself, but then again I only where my kilt on certain occasions. I would suggest that whenever possible you take your wife to some of the local highland/scottish events. Edmonton, Red Deer, High River, Calgary, and Canmore all have highland games. Sure they're not everyday situations, but it might help warm your wife up to the idea of wearing your kilt on non-occasion days.

-Will