Our gym locker room does not have cubicles it's completely open plan. I always turn to acknowledge people when I feel their presence behind me to let them know I know they're there and for my own comfort to get a visual on whoever is close to my person.
Standing at the sink in my underwear rinsing blood out of my workout pants I felt a presence behind me. I turned to acknowledge the person behind me and was very surprised to see a 6'4"+ 240lbs+ TW completely naked with a giant uncircumcised penis.
I squealed like a child, giggled oddly, and immediately apologized to the TW. For a split second I felt so guilty as if my natural reaction was cruel and not attached to some level of visceral fear.
I felt panicked, my heart began to race, I was feeling vulnerable, weak, and in a lot of pain for my period started while working out. I put my very wet workout pants back on and began to gather my things - and the TW was still standing there completely naked except now staring at me.
Since they were staring at me I felt it necessary to tell them "when in Rome do as the Romans" and "in the ladies rocker locker room that means avoiding full nudity as much as possible". This individual began screaming at me while naked calling me a Terf with penis swinging and I started crying like a little fuckwad. I left the locker room as fast as I could - the individual followed me out in a towel into the main gym area still screaming Terf and bigot at me.
The general manager treated me very poorly and told me that since I am a transphobe I should either use my home bathroom facilities or do a check of the locker room before using it to ensure that I wouldn't offend anyone with my presence.
Nothing crazy happened the TW didn't touch me or do anything to me beyond yell but they did chase me out of a space that was supposed to be meant for me - a biological woman.
I'm now fighting with the gym to get my annual membership canceled - my DH and mother have barked at me so much about not going back there as they are afraid that I will get to attacked in the parking lot. Their feelings may be a little extreme but as a woman and sexual assualt survivor I have learned to function on the side of caution.
This isn't about being a transphobe this is about sex-segregated spaces staying segregated for girls/women's safety -psychological, emotional, and physical. Because I'm nice I still wonder if my reaction to the TW was cruel and feel bad about the possibility of hurting their feelings... but my logical rational mind says I was the one made to feel uncomfortable and I was the one who became invisible as a class and visible as a bigot in the light of a man's desire to take over a space meant for me.
I expect some women possibly with larger stature than I or without a history of physical violence perpetrated upon them may feel differently but that doesn't invalidate my voice. Just because some are comfortable being in isolated spaces with someone twice their size wielding a penis doesn't mean that those of us that aren't should have to "suck it up".