OP- I'm so sorry you're going through this.
Of course I'm not telling you what's best for you, I don't know the details of your situation, but it may help to know that I grew up in a household where my parents slept in separate bedrooms and waited until I was 18 to get divorced for the exact reasons you stated.
I'd never express this to my parents (both now elderly) but I WISH they'd got divorced earlier. They thought they were hiding their pain and divorce would hurt me and my siblings, but actually it was written all over their faces every day in subtle ways (which kids can pick up on!) and it gave me a lot of issues I had to address through therapy as an adult.
I'm not saying you're causing damage to your kids, I just know that so many people with divorced parents end up saying that their parents divorce was the best thing that ever happened to their family.
You deserve affection and love which your husband can't give you. People have been asking how old you are, but my it doesn't really matter. My best friend just got divorced and started dating again with 3 kids at 53.
This may also be controversial to say on this forum, but your husband deserves happiness too and to be with someone who is interested in him while he's expressing his feminine side, and whatever that might end up looking like. It's sad when someone turns out to be different to who you thought they were, but it's never too late for both parties to find happiness (sorry for the cliche).
Wishing you the best of luck OP.