#373
It's not about sex, it's about gender. The pronouns you use to refer to people are just as easily derived from gender as they are from sex, so why not use the up to date medium? It's not like there is any rule saying you must refer to people as their birth sex. If someone looks like a girl to you but was born a boy why not call them she/her? I don't understand what's so hard.
Also, you act as if me being a woman is a "lie". I can assure you that I am a woman. I use the women's restroom daily - nobody once has told me to get out because I'm a liar. I don't think they would tell me that, even if they knew I was trans. Should I use the mens room instead? Would that be more appropriate, in your opinion? Please consider these types of things before you go and consider me a man. I can assure you with certainty that I definitely do not belong in a masculine gender role, because I am not a man.
You may argue "Well, you have to use the womens room, but you're still a liar!". This would obviously be bullshit, because I don't have to lie to anyone in order to use it. All I do is walk in looking like a woman and everyone goes about their day. There is no rule requiring me to prove that I am of the female sex before I use the womens room - only that myself and others can judge that I am enough of a woman to use it.