Some of these posts are unhelpful.
There are two separate issues.
One is the sexual politics of another person. Fair enough cross dressing is something around in society and isnt any thing to be ashamed of, really.
However, most of us in relationships where we didnt suspect it was an aspect would be in terrible shock at the discovery. It is also reasonable to make a decision not to be able to live with it.
And the OP said he was controlling. Certainly he hasnt been honest, and probably has all sorts of issues which have impacted on her, through his wish to contain this.
FWIW, OP, I have nothing at all against cross dressing. But if my own h was doing this, it would make me see him differently, and I would question all that went before between us. I wouldnt want to stay, either.
I did know a woman once, years ago, whose h came out as gay after a same sex affair. She wasnt anti gay at all, but her own self esteem was shit to shit, and she even obsessed about whether her own 'straight up and down' body type had been part of her initial attraction for him.
Poor you.
I do think you will get over this, and may be in time come to see more clearly than some that the relationship breakdown was nothing you could have prevented.