He is very lucky to have found someone as special as you Kate. I have always wondered as well why women can wear any male clothes they want but it’s taboo the other way around.
Please, please, please just this one thing if you are ok with him expressing himself, don’t change out of nowhere. Maybe set a limit or boundary but don’t go totally the other and shut down completely on him. It took lots of courage for him to share that with you which proves he has strong feelings for you and it matters.
I say this because my wife who was having fun with me expressing me did a 360 out of nowhere. She said she doesn’t want to be part of this anymore and I was just crushed because I felt lied to and a fool. She seemed to be having so much fun with me and and we would even go out, of course I was loving it. She used to buy me many things to wear and help with my makeup, nails and hair. Then POOF! I was so hurt and devastated. I tried talking to her about it but got nowhere.
Please be understanding and just have fun with it or as I said set boundaries