READERS, I need your help. This week's column is a problem-solver, and I'm hoping by the end of it, you might have the answer to a question that has left me absolutely bewildered.

Let's start at the beginning. Last week, I wrote a column about the Twitter departure of black feminist writer Claire Heuchan, who deactivated her account on the social platform after receiving abuse in the aftermath of a column she'd written about the relationship between Scottish nationalism and racism.

I argued that while I profoundly disagreed with her view, I absolutely defended her right to express it without having to deal with the hell of online trolling. That's a non-negotiable position for me. Women are routinely abused and harassed for raising their voices, and often the derogatory comments won't only be misogynistic, they'll be racist and homophobic, too.

As you will know, I've had some pretty extensive experience of this. Trolling is one thing, but things took a more serious turn a few years ago when a man was jailed for six months for a racially and religiously aggravated breach of the peace. The man had used an online podcast to embark on a racist tirade about me – based on my Irish heritage – and encourage his followers to abuse and harass me in the same vein.

Heuchan had, and still has, my full support on this: women must be able to speak without fear of repercussion.

So when she returned to Twitter earlier this week, I sent her a link to the column and told her I'd had similar experiences myself. But what happened next was utterly perplexing.

Heuchan responded, saying: "Sorry to hear you have experienced discrimination but, as you are white, that prejudice you faced was not racism."

I was stunned. Let's just roll back a little – the experience of the Irish in Scotland has been utterly shameful, and it was motivated by a blatant racism that retains strong traces throughout attitudes to this very day.

In the 1920s, the Church and Nation Committee of the Church of Scotland drew up a report called The Menace of the Irish Race To Our Scottish Nationality. The report stated: "Already there is bitter feeling among the Scottish working-classes against the Irish intruders. As the latter increase, and the Scottish people realise the seriousness of the menace to their own racial supremacy ..." It took the Church of Scotland until 2002 to apologise for it.

The barriers Irish people faced in Scotland are well documented. Indeed, the Irish only achieved occupational parity in 2001 in Glasgow. In New York, it was achieved in 1901.

To say I was shocked at Claire's rather brutal dismissal is an understatement. But it didn't stop there. She went on: "Claiming white people experience racism is actively harmful to people of colour. It erases how race functions as a hierarchy. A hierarchy from which white people benefit. All white people. Including you."

She added: "You expected me to centre white feelings above PoC's [people of colour] reality. That's how white supremacy maintains itself. Bye."

And then came the ultimate rejection, the tool of finality on social media which deems you to have crossed the line, which designates you persona non grata: I was blocked.

My jaw just about hit the floor. Here I was, having had literally years of racist abuse which has affected all aspects of my life, blocked for behaviour apparently bordering on white supremacy for having the cheek to mention it.

There are a lot of ways to look at me, and I expected Heuchan would look a lot further than skin colour. I am a woman, I am a daughter, I am a sister, I am a person.

I don't mind saying I was pretty hurt. I was under the impression that I was operating within, first and foremost, a feminist debate with women who respect one another's voices. That's certainly the spirit in which I wrote last week's column. To not only have my personal experience effectively excluded from the conversation, but to find myself completely blocked from it was hurtful.

Naturally, there was Twitter uproar. There were numbers from the Irish community infuriated that their experience was being erased from the picture. Others felt it was misleading of Heuchan to offer an analysis about racism and Scottish nationalism only a week before and then dismiss stories of racism perpetuated by unionists, despite the hard evidence of an actual conviction.

I’m still bewildered. It’s as though I’ve entered some parallel alt-universe where a public show of support and solidarity to a sister of colour is perceived as supremacy. And so readers, I return to my question and hope you can help – what the hell just happened?