It is tragic that you experienced sexual assault, and it is completely understandable and basic science that seeing a penis in the locker room might trigger you. Unfortunately, we cannot protect ourselves from the random triggers of the world. Have you ever considered that the woman you’re so resentful of for having a penis and being in the same space as you is also triggered by your vagina? Because she has had to deal with, as you say, a different experience regarding her womanhood? And it is womanhood. It is all womanhood. Your womanhood is experienced differently and not so differently from a trans person’s womanhood. But you do not get to dictate what is appropriate about their womanhood, what qualifies her to be a woman, or when she can claim womanhood to pursue her own happiness and safety (i.e. what you are trying to do).
Your reaction to seeing women with triggering body parts is exactly that; YOUR reaction. And as much as I sympathize with you as a survivor, you don’t get to use that as a way to scapegoat trans women. Your own individual triggers are things to discuss with your therapist. the world is full of things you won’t be able to control, all you can control is how you behave when you’re triggered. That’s the hard part of life. That’s what most trans women have to do all the time, to protect themselves from deep anger other women hold for them. I’m sorry you’re angry, but that doesn’t mean you can take away someone else’s female safe space. You’re not God, you’re not the one who decides what womanhood is. You don’t even decide what a safe space is (some women have been raped by women and thus a safe space for them is not a locker room). Trans women experience rapes at much higher rates than any other marginalized group, and yet instead of finding empathy and perhaps even solace in another woman who has experienced something you have, you’re letting your anger about the trigger’s mere existence get in the way. I wish you the best, and lots of help, because right now you are more harmful than helpful.