Hi Rae,
I’m in a similar situation to you. My partner of 6 years whom I recently bought a house with came out as non-binary recently, started dressing very feminine at home, waxing and using they/them pronouns.
It’s been a lot. I definitely feel the aloneness. They are out with all of our friends and I still feel alone. I don’t want to be the one complaining and making this all about me because they’re also going through a lot. But it’s a massive change for me.
All that being said I have a lot of hope. We love each other deeply and are committed to making it work and I’m confident we can. We also are about to (re)start couples counseling which was immensely helpful in the past. If that’s financially feasible for you I completely recommend it, would give you a space to be heard and just get at more of what’s going on in his head to give you a better sense of how much might change.
I’m new to this forum too but feel free to message me and we can commiserate about how hard this is.

Also:  just started listening to the our voices podcast about cis female partners of MTF people and found it helpful.

Best
Courtney