no amount of hormones injections and surgeries will actually change your love.
Well actually, yes, it will. Sure it won't change your DNA, but if you feel, look, and act like a member of that love then you are just as much a part of it as anyone else.
You also act like it's some terrible thing to want to be another love, when in reality it isn't. There is a huge difference between being morbidly obese or morbidly skinny and wanting to be a different love. The first two are actually unhealthy and put you at risk of heart attack and other complications, while the other is just in the head. There's also a difference between being schizophrenic and wanting to be a different love. One makes you have hallucinations and paranoia, the other just makes you uncomfortable in your body.
By agreeing to call them by their preferred gender, you're making them comfortable and helping them better control the discomfort they experience, it's as if you're giving them a bit of medicine to help them. Much different than telling a schizophrenic person their delusions are real, which instead of helping actually makes things worse.