Maria,
On the bright side, your wife is the champ here- really stretching to help you. I suppose she now knows better just how difficult and emotion-laden this is for you. You are writing it all out bc you wanted to do it, right? But you 'couldn't'- which only means that you felt a threat still existed that was too great. So maybe work on that. There will be more dresses, and more opportunities, but all of them will be missed until
you work on identifying what that threat is and whether you really have to honor it.

I no longer care who knows- I came to it gradually, but I realized that the shame is taught us as a control measure, and it is punitive and traumatic and cruel. I had to forgive my parents a lot of things, and this was one of the smaller ones- since I knew at heart I was harmless.

My guess is that the main threat was that 'someone' would come in and see you. Even if you were just in the dressing room, someone would come in and figure it out You realized the sales girl didn't care, your wife was saying clearly she wanted you to enjoy it, but you knew that it was still possible that someone would see you and then the SECRET would be out.

You were justifiably panicked- your wife was talking OUT LOUD in public- not acting like it is the SECRET that must never get out.

You were right- as long as you feel that way, you need to keep it a secret in a careful way.

But you might find yourself in the same situation on your drive if some drunk driver sideswipes you or you hit a deer or whatever. You have made peace with your chances in these situations, or the coffee shop? but maybe that has to do with having your wig and at least not looking really stupid - i.e. like a guy wearing a dress without realizing he had to do a lot more to earn basic respect for his humanity!

Your wife seems quite generous in terms of trying to accommodate your needs, so maybe you can get a nice win out of this moment by thanking her and having her help you by talking more out loud about how you feel. What you wish for, what you fear, what you worry she will feel, etc.