“A mistress is not a 'homewrecker'. She never promised to protect another woman’s home.”

“Stay away from my husband.”

“Such a homewrecker.”

“She’s a husband-stealer.”

Men are there for the taking. They’re just haplessly dangling by their wedding rings, waiting to be picked off by scarlet-clawed, predatory hussies who want nothing more than to ruin another woman’s life.

That’s the narrative that flourishes around any news story where a Married Man and an Unmarried Woman have sex, and – surprise, surprise – things end badly.

This week, those roles have been filled by media company Seven West’s CEO Tim Worner and Amber Harrison – the woman who worked down the corridor and became his lover for two years before their affair exploded in a mess of ugly accusations, disputed financial settlements and a splatter of egg on faces.

Worner is 55 and married. He and his family of six live on Sydney's northern beaches, in a white-and-glass home worth almost $10million.

Amber Harrison is 37. At the time of the "thrilling" affair she and Worner conducted in secret, she was single.

They worked in the same building, and Harrison says Worner would regularly walk past her in the the hallway without so much as a "hello". Meanwhile - she says - they would regularly get company-funded taxis back to her Sydney home to have sex.

Things allegedly went pear-shaped when Harrison's mental health began to "unravel", and she ended up leaving Seven with a $150,ooo payout and a promise of more money to come. It never came. And here we are, with a court case and dirt flying and a grown, married man being forced to deny that for him, this was not a pattern of behaviour.

Nobody comes out of this story looking great. With the exception of Worner's wife and children, there is no-one blameless in this situation - not the bosses who allegedly tried to cover the mess up, not the executive being paid $2.6million a year, and not the woman who slept with him.

No-one is covering themselves in glory here.

So why is it the "husband-stealer" who is feeling the full force of the blowtorch online?

Because "the mistress" always does.

Never mind that it was not her who stood beside one other person and promised to love and honour them, forsaking all others.

Never mind that they, as single people, were not the ones who made a commitment to put the well-being of one other person above their own.

And never mind that they are not the one who's lying. Taking their phone into the bathroom. Keeping a spare shirt at the office.

In the Worner case - as in all others where one person is committed and the other is not - the weight of the betrayal lies not with the "other woman" but with the person breaking the commitment.

As a married person it is YOUR responsibility not to hurt your partner. You promised that you wouldn't.

The "other woman"? She never made such a promise.

Flip the gender roles in these stories. If you - as a 'married' woman - are being chatted up at the pub by a single guy, who is responsible for you not betraying your partner? Is it him? Or is it you?

Did the stranger in the bar - or the EA down the hall - make a promise to your spouse? No. You did. That's on you.

The sisterhood is a wonderful thing - in a Utopian world, all women would treat other women how they would like to be treated. And each of us draws that line for ourselves.

But when that line is smudged, perhaps erased, the responsibility for cheating lies with the cheater.

Amber Harrison - and all the Amber Harrisons - made a bad decision when she went to bed with a married man. A stupid decision. A selfish decision.

But it's the man with the ring on his finger - or in his pocket - who betrayed his wife.