"Women who sleep with your man knowingly, should never be forgiven. Ever."

Columnist and celebrity Vogue Williams (who happens to be the ex-wife of Brian McFadden) said she doesn’t forgive the woman who kissed her husband.

“Being with someone in a relationship breaks girl code,” she wrote in The Independent the weekend.

“If someone didn’t know a man was attached and was completely honest in their mistake, then I could personally forgive that girl, not so much the person I was with though,” Williams said. “The only thing I couldn’t forgive is a girl who knows a man is with someone and still chooses to go there anyway.”

It takes two to cheat. but it’s usually one that is scorned. The woman.

She’s the woman who stole my husband.

Does she have no self-respect? 

How could she? 

The ‘other woman’ is loathed, feared, laughed at, pitied, branded, blamed.

This is understandable. It’s certainly easier to be angry at a woman you don’t know, or who means nothing to you, as opposed to your husband of 15 years or boyfriend of 12 months. Blaming the mistress can be a convenient outlet for hurt, grief and insecurity.

But is it fair?

When a women doesn’t know a man is in a relationship, the responsibility of protecting that relationship falls 100% to the husband or boyfriend. But, when she knows of the relationship, does that relationship become her responsibility also? Even though he’s likely to be equally keen, persuasive and seductive in both situations (arguably more so, when trying to convince a woman to sleep with a married man)?

Certainly, we do expect some level of comradery from our sisters. And, theoretically, a ‘girl code’ is a nice idea. But, considering the myriad of emotions, reasons and motivations involved in starting a physical affair (regardless if the person is married or not) is it fair to say sleeping with another woman’s husband is always ‘unforgivable’?

Maybe she’s in love, maybe he’s fuelling that. Maybe she doesn’t’ want commitment, so sleeping with someone who’s already got a ring on their finger is exactly what she’s after. Maybe it’s the thrill, or the chemistry or the accessibility. Maybe she started it, maybe he did. Either way, it was his relationship, not hers.

But when you’re the cheated one. None of these reasons matter, and our blame for the ‘other women’ can be scathing.

Take, for example, the speculation around “Becky with the good hair” following the release of Beyonce’s album Lemonade, where she alludes to the infidelity of her husband Jay Z. The reaction of the public and media to the possible mistress was exactly the same as Williams’ – unforgiving. When fashion designer Rachel Roy posted a photo to Instagram with the caption “good hair, don’t care”, the haters descended, commenting on the photo, changing Roy’s Wikipedia name to “Rachel Roach” and shaming her across all social media platforms.

Similarly, Anglina Jolie was held accountable for the split of sweethearts Brad Pitt and Jennifer Aniston in 2005. She faced huge backlash from tabloid media, and the realities of Aniston and Pitt's marriage - that he was taking drugs and unhappy for other, unrelated reasons - was irrelevant when put beside the glaring, sexy, extremely-easy-to-blame presence of Angelina.

Monica Lewinsky, of course, was arguably the first celebrity public 'other woman' and the hounding she received from the public and media forced her into hiding. It is only now, eight years later, that she's speaking out against the bullying and abuse she faced as that woman.

Infidelity is common - it's estimated around 60% of men have reported having an affair at some point during their marriage. From these infidelities, the man himself is likely to face some tough questions, but the reputation of 'other women' can be absolutely torn to shreds.

William's story is not unique. She's not the first woman who's husband has kissed another. But the intricacies of her relationship with her husband, and the reasons and motivations behind his affair, are unique.

It's likely the reasons for that kiss have more to do with his marriage with Williams, than they do with the girl involved. It is definitely Williams' prerogative to "never forgive" the actions of that woman, and she's arguably justified in doing so.

But putting any woman's behaviour down to "breaking a girl code" is overlooking the complexities of human emotion and the labyrinth of reasons and circumstances that can lead to infidelity.

It was, after all, not the 'other woman's' relationship to protect.