At a basic level I told her because I didn't want to lie to her or keep secrets, but there is something to your comments. Until the past couple of weeks it had been over 15 years since I'd dressed at all and in some ways I do want to make up for lost time. Acceptance would be nice too, and that was hard to predict as my wife is quite open minded in some ways, but does also have a conservative streak.
Thanks for your advice on this, I will indeed tread carefully.