Bruce, Caitlyn and the Death of Neutrality

I grew up seeing Bruce Jenner on Wheaties boxes for his success in the 1976 Olympic decathlon, but I had largely forgotten the name until Bruce emerged in the media this week as Caitlyn Jenner, having undergone transgender surgery. One question this has birthed is whether to identify Caitlyn Jenner as the winner of Olympic gold. However, everyone is clear regarding the present: Caitlyn expects to be called Caitlyn, and not Bruce. Using the name "Bruce" intentionally would be an insulting rejection of this new identity.

This is a halachic question. There is decades-old debate in Jewish law regarding the male/female status of someone who has undergone transgender surgery, but it is clear that halachah prohibits a male from undergoing such surgery, since the Torah explicitly prohibits the removal of male genitalia (Vayikra 22:24, Shabbat 110b). So if I were to meet Bruce/Caitlyn, would it be halachically incorrect for me to say, "Hello Caitlyn"? Would I be endorsing a biblical transgression?

The same question comes up in relating to the quite-common phenomenon of intermarried Jews. Is it appropriate to invite a Jewish man and his non-Jewish wife to a wedding, addressing the invitation to "Mr. and Mrs."?

Of course, a halachah-abiding Jew never wishes to insult and hurt people. And let's not be cynical; saying Bruce would hurt Caitlyn. I cannot imagine the depth of the feelings of a morphological male who believes himself to be herself, and who would go under the knife in such dramatic ways to gain a new image. But does that justify counterfeiting Jewish law, by approving of that which Jewish law forbids?

In truth, this question is old. In one example, a millenia-old mishnah talks about how a Jew should relate to another Jew who farms illegally during the shemitah (Sabbatical) year. This mishnah teaches that one may not "strengthen their hand" by encouraging them in their activity - but that one must promote peace and greet them with a "Shalom aleichem". (Mishnah Sheviit 5:9)

In other words, the mishnah instructs us to keep the peace, by greeting warmly but withholding approval.

However, there is a new, complicating element: the death of neutrality. Perhaps one could have maintained an inoffensive ground in the past and everyone would have understood, and hopefully respected, the tactful disagreement. Today, though, there is no middle ground; speaking with Bruce/Caitlyn and awkwardly avoiding use of a first name or a gender-specific pronoun would be perceived as an insult. [Indeed, don't we often expect non-Jewish society's approval, and reject their neutrality, for our choices as Jews?] And so we are told to choose: Are you with us, or are you against us?

I am not sure what to conclude on this point; I'm still looking for relevant halachic background, and thinking it through. [Update 6:50 AM: To clarify: My current inclination is to say that one would not be justified in using Caitlyn. But I think there are nuances to discuss - for example, is this surgery halachically irreversible, such that the problem of lifnei iver (causing the blind to stumble) might be less relevant)?] Either way, I think this new element - a modern intolerance and sense of entitlement, in which our personal decisions must be accepted and approved of by third parties - is worth contemplating. On one hand, I don't want to voice approval, coerced or not. On the other hand, isn't preservation of peace a great value?

How would you greet a transgender relative? And do you have a Torah source to back it up?