"There's no good guys or bad guys in this situation. There's just people stuck in an incredibly difficult situation with no easy answers."
Yes. That is unfortunately true. Speaking as a woman who has been in more than a few serious ltr's with men, and married more than once, again to a man, l feel like l can understand the POV of a woman whose man (?) wants to become a woman, (or just as bad), wants to castrate himself.
In my mind, in my heart, that would be tantamount to losing the man l loved and married. That, l believe is why your wife was crying. Sure, you can convince yourself and maybe even your wife, that you will still be the same person "inside". I don't believe that. Based on my own experience and the words of others, everything changes.