One more thing:
About the "he's still the same person inside!", which, like the suicide threat or the epithet of "transphobic," is often used as a cudgel to convince a wife she ought to stay with a transitioning spouse.
Actually, no, he's not the same person. That reasoning assumes that the only difference is cosmeticmake-up, jewelry, and a dressbut all else is unaltered.
In fact, the entire reason a person says they want to transition is that the person they've been presenting as is not the person they wish to become or that they believe they are. They want to be someone different--the "real" person as opposed to the, apparently, fake one you've been married to, or, in my ex's case, the one he says he was never allowed to become. Once they transition, they don't want to be called by their "dead name" and they often begin to express a personality that is quite different from the one of the man you married.
And as with the suicide threat, we could turn that around: if the transitioning person is "still the same person inside," then why does s/he need to transition? If a spouse is supposed to ignore the outer package as irrelevant, why is it allowed to be supremely relevant to the transitioning spouse.
IMHO, once a spouse begins transition, the default ought to be that the marriage is dissolved. That would save a lot of transwidows from the pressure under which too many are convinced to stay when it is not in their own best interest.