Welcome from the highlands of North Atlanta.
You might try taking your wife with you to places like the Highland Games and Scottish Festivals where lots of guys are wearing kilts. She will see that you are not alone in your love for the kilt and that lots of guys do own and wear kilts. My wife doesn't go to the festivals with me but I take a lot of pictures to show her. As she becomes used to seeing the kilt on others she will become more comfortable with you wearing the kilt.
Don't push the envelope on the regimental bit, the battle isn't worth fighting with your wife. As Turpin said, honor her wishes, beside, there are also some benefits for you.
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