Men are statistically more likely to sexually assault children than women are. But we don't prevent male teachers from taking up their positions, do we? We aren't campaigning to remove men from primary schools. And nor should we. Bad people will do bad things, but it shouldn't stop us trusting people as a whole.
Let me also start by saying that what happened to you was terrible and that it should never have happened, FrackOff 
I would like to address your statement, because for me that represents an upside down way of looking at the issue of male sexual and physical violence.
Abusers often choose professions that allow them to target the most vulnerable of their preferred type of victim by putting themselves in a position of power over them. This is well known and documented, with many cases having been tried at court.
Male offenders make up about 98% of sexual predators, this is also a documented fact.
To protect vulnerable people, we have put into place systems, rules, regulations and practices aimed at a) preventing known abusers from working with such groups and b) minimise any opportunity that could be used by abusers for their own purposes.
You're right, we're not stopping all men from becoming teachers, but we have put measures in place seeking to stop those men who are abusers from becoming teachers in the first place and if that fails we're seeking to stop them from being able to exploit vulnerable situations.
Safeguarding doesn't work by putting one safety fence up keeping out the bad guys because every fence has its weak points. Instead, as another Mumsnetter said, we're using a Swiss cheese approach by layering many different safeguarding measures on top of each other. And like a block of many slices of Swiss cheese, eventually all of the holes are covered.
Sex segregation where we are vulnerable or in a state of undress is one of these layers. It is one of the most effective tools we have in protecting ourselves from male predators. The taboo of a man entering certain female-only public spaces used to be so strong, even domestic abusers for instance would stay outside the door to the ladies. Because he could be sure to be challenged and stopped from going in. Not just by other women, but also by other men.
There is no evidence that a male who identifies as trans poses less of a risk to females than any other male. There is a lot of evidence that the former poses the exact same risk as the latter.
This is why we oppose turning female-only spaces into mixed-sex spaces by allowing males who identify as trans access. This is why we insist on applying normal safeguarding rules to them.
Please note that now absolutely no changes at all are required from males who wish to claim a trans identity and with that access to female-only spaces, services and facilities.
No name changes, no pronouns, no presentation, no clothing, no behaviour - no "living in role" at all. No medical diagnosis. No proof required.
The only thing a man called Kevin, who looks exactly like any other man you have ever met, needs do is to utter the magic words "I identify as a woman" and we must then accept Kevin is a woman.
Given this new dogma, and the fact that we cannot identify any abuser by looking at them, it is even less logical to exempt such males - any males - from the safeguarding frameworks set up to protect us from male violence.
And yet, we are being asked to do just that. How do you justify such an approach?