My memoir about being a “spinster” came out last March.

For every one of the countless appearances I made to promote it, here and internationally, I prepared for a particular question.

It never came, and I forgot to prompt it. In its absence lurked an ineffable, gagging, dare we speak of it, silence. Until last week.

Since I am 66, I was invited to be a panellist at the Flesh After Fifty Festival in Melbourne. It was there that the silence broke. The question came and I said yes, I was sexually assaulted.

A producer preparing me for an interview did once ask, confidentially, if I thought I was a spinster because I had been assaulted. Her question disturbed me. I included my stories to dispel this very myth.

There is no automatic connection between rape and spinsterhood, though individual spinsters may choose against, or find sex abhorrent as a result. Women couple and have children regardless of their sexual assault. That’s how resilient we are.

My first assault occurred in Perth, in the 1970s.

The rapist was a student at the University of Western Australia, a member of the debating club, he went to an elite boys school, and, you guessed it, became a high-profile figure.

He is not – repeat not – our Attorney-General. However, throughout university, I was sexually harassed by men with similar backgrounds who went on to hold high office.

Such is the treacherous soup through which girls swim to womanhood in Australia.

I deliberately wrapped my assaults in a muscular armour and kept my silence until I healed. My silence was crucial, precious, empowering. An important silence to keep. Better not to speak if the wound is raw. Speak only if doing so salves the pain.

It’s a great paradox of life. There’s no one way to heal.

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But here’s a thing: I also kept quiet for fear of losing the respect of my family and friends. For all the freedom of the Seventies, the onus of rape was on the woman. That she engaged with men was enough for her to be regarded as culpable – forget being attractive, drunk, out at night, or what she wore.

I never expected justice from the police. Nevertheless, I chose against pressing charges because I didn’t seek this man’s punishment. I wanted sexual harassment and assault in Australia to end, for women and for men. This remains impossible to achieve through the courts.

When the #MeToo movement broke on American shores, I re-interrogated my decision not to name this man or lay charges. Again, I decided against doing both. For me, there is no point to engage a system that continues not to deliver justice.

All this got me thinking about mothering boys through the ’80s. God knows, I read a lot about feminist mothering in my twenties. But how to mother sons in that wretched soup is the question. Many of those mothers must have kept their silence too. Many may have had nothing to keep silent about.

But I can’t help wonder, if I had a boy could I have protected him against the hazing rituals and rampant misogyny in our elite schools and universities? I’m not sure I could have.

These days ring with clarion calls from our daughters and granddaughters. They want justice for women.

It distresses me that they fight a battle we might have won 40 years ago if it weren’t for the silence many of us had to keep.

Silence is a tricky thing. It heals and protects. But it also ambushes those who would bring down patriarchy.

Today we march. Today this old woman adds her voice to the outrage, because I can.

I am sorry my silence has been long, but the time has impassioned me to speak.

I will never say my rapist’s name, but now I stand beside you, brave daughters and granddaughters of Australia, and speak of what he did to me, too.

Donna Ward is a writer, editor and author of She I Dare Not Name: A Spinster’s Meditations on Life (Allen & Unwin). She is also a psychotherapist and social worker