Whenever I kilt up I get asked the same question---What is the special occasion?--by my beloved, as she believes that I should only wear the kilt when there is a specific scottish/celtic reason to wear it---namely a games, a kilt night, or other scottish specific gathering. She is not fond of me wearing the kilt, and does not think it at all masculine, jokes regulalry about it being a skirt (although this is diminishing), and actually says out loud that it turns her OFF from a sexual interest standpoint. On top of that we regulalry battle about my desiring to wear a kilt to significant events where she would be expected to accompany me, rolling her eyes and sighing as if her attending by my kilted side has now become more of a chore than a pleasure, simply because I chose to attend kilted.
We met, dated several years, were married three years and were having our first child together before I was bitten by the bug more than 4 years ago, and she openly says that if she had known I was going to start wearing kilts (sometimes she says skirts) that she would never have married me. Not an ideal situation to be in for one who desires to maintain a happy marriage yet still wear the kilt when he feels the urge. There have been a couple occasions where she has threatened not to attend an event with me if I went kilted, to which I said I would then attend the events alone and kilted, which eventually prompted a reluctant change of heart, but not attitude.

Oh well, for some it is easier than others. Best of luck, and realize that you are not alone and are in good company. I have no suggestions to give you, as only you can know your spouse's particular situation and feelings and how best to approach the issue with her. Many of the above stated ideas may work for some, not for others, and frankly backfire for a few. I can only suggest trial and error, patience, kindness and consideration, and ask for the same from your spouse.

jeff