The first time I was sexually assaulted on public transport, I was 12 years old. Though at the time I wasn’t sure whether I had been. Like many young women, I’ve never felt too confident in calling out these events with certainty.

At the time I was sitting on the lower deck of the bus on my way to school. I was in school uniform; a navy jumper emblazoned with a white crest saying something in Latin about hard work. I sat uncomfortably as a man next to me began to caress my leg. Just the thigh, no further, but clearly an inappropriately close interaction. I was frozen – not necessarily with dread, but confusion. Was he doing it accidentally? Maybe I was just being sensitive, he seemed so calm, and nobody else seemed to notice.

Like every time it has happened since, the memory comes to me in strange sepia tones where I feel like a bystander watching in horror from the outside – unlike my other full-colour memories.

I still feel disbelief that what happened could have really happened. The questions I have are ones that have probably been asked by the many women who don’t report sexual assault on public transport – although a drive to encourage reporting has led to a doubling in the number of recorded incidents over the last five years. This is a good thing: women need to feel empowered to enforce their right not to be harassed or assaulted in public.

But the many variables, including alcohol, in these situations can often make them feel harder to call out. I remember one Friday night shortly after graduating, fully equipped with all my feminist mantra, ready to fight the patriarchy, when a man in the street thwacked me across my bum. When a friend asked me whether that had really, actually just happened, I was a little confused. I hadn’t yet conceptualised that sexual assault can feel like normal and inescapable behaviour in certain situations.

When I raise the issue of sexual harassment, the response from men is normally to ask, cautiously and very sympathetically, whether this has happened to me. The response of other women, by contrast, is invariably a swapping of stories; counter-tactics that have been helpful; or a list of all the women they know it has happened to, of all ages. Despite the empathy and the sense of horror, it’s clear that half the population has almost no idea of the scale of this problem.

Another response has been to ask why women don’t report incidents, particularly the seemingly unambiguous ones. People can understand how, perhaps when pressed up against someone on a packed train, a person might be unsure about whether to complain, but what about the clear examples? Sadly, the distinction between the two doesn’t quite pan out in reality. Sitting at the back of the bus, this time after school, I sat horrified as a man placed a newspaper over his penis and began to masturbate. But I didn’t feel angry, I just felt like an inconvenience. I looked down at my shoes and then out of the window – almost as if trying not to disturb him. When I looked directly at him for a moment, I was met with a nonchalant stare. His complacency made me feel ashamed at having the temerity to be there.

Witnessing such a private act in public is such a bizarre thing to happen that you can’t help but question whether it really is an assault. Other power dynamics operate too: about a woman’s place in society, and whether being offended makes you arrogant in some way – as if to believe you’ve been the subject of sexual harassment is to claim you are the object of irresistible sexual desire. If that sounds incomprehensible, you only have to look to Donald Trump’s belittling of the woman who alleged that he had sexually assaulted her, on the basis that she was too ugly for him to have done that. It is for these reasons that I have never, despite the umpteen times it has happened, reported an instance of sexual harassment or assault in public places against me.

It’s often claimed that these things happen only to certain women. But in fact, every woman I know – from my younger sister who is still at university, to friends’ mothers, well into their 60s – has experienced some kind of sexual harassment. Laura Bates’s Everyday Sexism project, showing just the same has highlighted the scale of harassment. It is something that happens regardless of who is around – like the times that multiple friends and I have been singled out or even chased in public in broad daylight.

Worst of all, it is something that happened most frequently to me and my friends in the days when we wore school uniform. The fact that it tailed off when I hit sixth form, when I was less obviously signposted as a child, leaves a lingering feeling that there were more sinister dynamics at play.

But at least there’s now a chance to create a culture of normality around reporting such offences. A few years ago, a friend’s mother jokingly told of how she ordered a man on the train to “put that ugly thing away”, and he obeyed. The story made me envy her courage but I could not help blaming myself for having so often feared the repercussions of responding similarly. The news that more incidents are being reported hopefully gives women a different escape route: to hold those responsible to account without endangering themselves.