This discussion is ultimately always pointless and I guarantee that it will devolve into a circus so let me make some things clear before it continues any further:
1. Some people respond positively to sex reassignment surgery whereas others don't. In the future this likely shouldn't be an issue so long as people are able to seamlessly alter their bodies as they wish. As for now, how to distinguish who sex reassignment helps from those it harms is a problem for psychologists to resolve, not us.
2. Transgenderism and gender politics in general isn't inherently revolutionary and can be just as reactionary as it's opposition.
3. If you want to be friends with a trans person you should probably respect their pronouns. Even if you disagree with it, you should already understand how everyone has quirks and hangups that you have to adapt to.
4. There should either be a single washroom for any sex to use or a third sex-neutral washroom.
5. Trans people are human beings and are thus capable of being horrible people, don't dehumanize them by denying them such. But try not to become an asshole in response and alienate the trans people who are wonderful.
6. The vast majority of people don't give a fuck about any of this shit and are either indifferent, accepting or suspicious of it. Trans people make up a tiny percentage of the population and it's safe to say that most of them are otherwise normal people. The crazies are overrepresented by Twitter retardation and obsessive /pol/acks.
7. Trans issues are extremely overblown and incredibly degenerate in modern discourse, and like most cultural issues are used as little more than a political tool by cynical elites on both sides. By obsessing over it instead of trying to go beyond it, you are playing into their hands. Don't allow yourself to fetishize or antagonise trans people, that's exactly what they want you to do.
8. Our primary goal as socialists and communists ought to be overcoming capitalism, not changing culture; we aren't hippies. Focusing on trans issues is almost absolutely just bikeshedding (
https://en.wiktionary.org/wiki/bikeshedding).
9. There is no truth to "feeling like a woman" beyond how a woman is subjectively defined by yourself and those you relate to.
10. Gender only materially exists insofar as the sexes can be assigned certain roles for their physiological ability in relationship to the needs of society. A man is usually stronger than a woman so a man hunts and does difficult labour, but most people don't hunt anymore and difficult labour is becoming more obsolete. A woman has children and is vulnerable, but that vulnerability becomes less severe as daily life becomes safer. The materially origins of gender will be mostly abolished when the physiological differences between men and women are overcome, and from there it's just a problem of ideology.
One point of clarification for 10: the reason why I use "gender" instead of just "sex roles" with regards to the material origins of gender is that such roles are intentionally fluid despite being otherwise rigid. The reason why is simply that if lots of men in a tribe go missing or are killed off, the remaining women have to take up their roles. There is plenty of evidence for this and vice-versa throughout human history, and I must repeat once again that such roles are slowly becoming subverted as socially necessary physiological differences are rendered more and more obsolete by technological advancement.