I think it has most to do with an abject fear of rejection. On the one hand you can't help your need to dress, but on the other you feel that if you do you'll lose everything that you hold dear. Maybe a part of it also has to do with the way you and all other guys are socialized and have formed your male identities, by rejecting everything feminine, at least publicly so in your case. So you've had some internal conflict to resolve as well as dealing with a fear of losing wife, family, friends, etc.
It's not easy.
So ... now that she knows, please guard against going overboard in the opposite direction if you can. I've seen it happen here often enough, like the cover that comes off of a steam cooker. This is understandable, and usually things get back to a more balanced state down the road, but the immediate swing to the left does scare many of the wives who all of a sudden go from thinking their husbands like to dress occasionally and privately, to wanting to do little else but, including body shaving, nail growing, eyebrow plucking, ear piercing, along with tons of new clothing and accessory purchases, in order to begin going out dressed in the mainstream (if they had been previously closely closeted). In other words, *pink fog*. This is when a wife might wonder what is happening to her husband and her marriage, and she might wish to stop supporting the CDing because she'll be scared. Or, she'll do her best to seem supportive while she struggles inside and wonders what is going on.
Don't forget that it will take your wife just as long as it took you to reach the same level of acceptance you're at now, so please don't go faster than she can catch up.