I am so sorry, Michelle. I haven't had that experience personally, because everyone in my life so far (except my father, but screw him) has been super supportive. My fiancee, though, just came out to me and the polyfamily this week. I've known her for over a decade, and I had suspected she was trans by a lot of little tells. My girlfriend Nameera, who had been involved with her previously, remembers a time around 2000 when Thorne broke down in tears, telling her that she hated being male, she hated having a penis, and she felt like a lesbian trapped in a man's body.
Nameera went to Thorne's wife of the time, Cat, and told her about this. Cat freaked out, accused Nameera of lying, insisted that Thorne was "all man", and that if she was wrong and Thorne decided to transition, Cat would divorce her, take the children, and Thorne would never see them again. As they were living in the Deep South, Cat probably could have done just that.
So Thorne coming out was a big deal, and our polyfamily and close circle of trusted friends have been nothing but accepting of her. We love her, and we love that she now feels she can be open about who she is, even if she's scared. I hate what was done to her by her ex-wife and family of origin, and I hate what your wife is doing to you.
I wish that this wasn't happening to you. I'm glad that you're able to roll with the punches, make plans, and that you're staying true to yourself in spite of all this. I hope that you will be able to share custody and still have time with your daughter, and that she will be supportive of you through your transition. I wish for all the good things for you, and you have my total support.
*hugs and cookies offered*