But Datun I don't think anyone can tell she's male? She's 5'6 and looks really feminine - she had the surgery when she 22 and had been on hormones for a couple of years before that.
The thing is, Princess, this isn't, and never has been, about individuals.
We do not make laws based on the people who won't break them. We don't make rape laws based on men who won't rape.
You can have personal empathy for your friend (and why wouldn't you), whilst understanding that as a group, men are harmful to women, including those who identify as women.
It might be an uncomfortable position to occupy, but it's rational. We have to have customs and protocols based on group analysis, not individual analysis. Which is why you then go on to say this:
I think my experience at the theatre is what's really brought this into sharp reality for me. I know it's irrational but I feel scared at the thought of sharing the loos with someone who is/looks male
This is entirely rational, of course. Your experience of men is the same as anyone else's.
You may not know the statistics, but you know the experience.
Women are routinely catcalled, steet harassed, sexually harassed, assaulted, groped, leched at, raped and murdered. The #MeToo campaign ran to 11,000,000 posts in under 24 hours.
And it's not by other women.
Men commit 98% of all sex crime and 90% of violent crime.
It doesn't mean that we think all men are predatory. It does mean that when we are in a vulnerable position (in prison, half naked, in hospital), we want to eliminate as much anxiety and risk as possible. It's instinctive. And statistically evidenced.
You're displaying empathy for a friend. You can do that, whilst maintaining the position that certain spaces should be segregated by sex, and that includes your friend.