My advise is to make it a non issue. Call it a skirt yourself to show that the skirt word holds no insult power. Just wear it. Show her you are the same man she fell in love with and that nothing has changed in you life but a little more comfort and a little more style. Give her some ownership in the kilt. Let her help you pick out a sporran or other accessories that make it look less like a woman's skirt. Show some manly men in kilts and ask if this sporran would be best or these shoes etc.

My wife thought it was weird at first but now loves the kilt.

Most of all don't let it ruin your enjoyment of the kilt.

Mark Keeney