I have had the "revealing for the first time" moment about three times over now
I've been very lucky, there have been 3 women at different parts of my life who accepted this side of myself and tried their hand at Mommying me
There were slight similarities between the three experiences; nervousness, awkwardness, bashfulness and yes, vulnerability is a big one as well, for those of us who view this as a part of who we are or a genuine lifestyle it's hard not to feel vulnerable, this is such a personal, emotional and private side of ourselves, we are exposing our soft underbelly to someone new, we just want to be loved, cuddled and cared for, but at the same time we are always worried about being hurt.
With my first GF/Mommy I was so nervous, I took forever to get my diaper on and I was even fumbling with the tapes. When I left the bathroom, there I was, in nothing but a diaper, clutching a stuffy and sucking a paci. I felt warm and tense and maybe even a little silly, but her reaction was just sort of... eh
She didn't react any differently, treated it like no big deal and that took the edge off a bit. When it got to cuddling, it was a little awkward for both of us. Overtime I was able to loosen up with her, but I think she was always worried about doing a good enough job, she was timid with most things let alone looking after a colossal bABy, but I always appreciated her efforts
With my Mommy friend, it had been ages since someone had seen me in that position and that was my first time being diapered by someone else on the first reveal. I remember feeling nervous and rather embarrassed. I was also questioning, I wondered about what she thought, I wondered if she was gonna diaper me properly, my mind was going a mile a minute
My Mommy friend was very proactive though, she took initiative and went out of her way to make the experience feel natural and pleasant for both of us, so it was a much more mutually relaxing experience with her
My current Mommy/GF is a godsend, she's absolutely great. We are long distance, so the first time she saw me regressed was over a video-chat, and according to her, it was love at first sight
She cooed and complimented me and we just talked about the nature of this side of myself and our plans for the future. Our consistent Skype calls and conversations broke the down the barriers a bit, we got to know and become comfortable with one another, emotionally in-tune, so when I got to be babied by her in person last month, everything came quite naturally for the both of us. It was a wonderful experience/feeling; complete and utter acceptance, comfort and security
So yeah, I'm glad your wife is accepting. The first experience tends to be all-over the map, it's a bit nerve-racking, tense, awkward and vulnerable at the same time, but if you are revealing this side of yourself to the right person, it can very quickly become an incredibly sweet, pleasant and mutually fulfilling experience
It also goes without saying, but the more she sees you like that, the more natural and understanding your dynamic will become