Ms Onus-Williams came under fire after her impassioned speech on January 26, in which she said she hoped Australia would 'burn to the ground', left many conservatives outraged.
Calls for the 24-year-old to be stood down from her role with a government-funded body have been met with anger, and since turned into an outpouring of support online.
A distressed Ms Onus-Williams told NITV News the events of the last few days had taken a toll.
"I'm very overwhelmed," she said.
As a response, many prominent Australians have taken to Twitter to show their solidarity with the young activist by using the hashtag #IStandWithTarneen, which has been trending on the social media platform since Tuesday afternoon.
Indigenous newspaper, Koori Mail, said they stand with Ms Onus-Williams 'because the voices of Black women need to be heard, not silenced,' and feminist Clementine Ford said free speech is 'extremely selective' when it comes to racists, homophobes, transphobes and misogynists.
Many others have come to Ms Onus-Williams' defence, labelling the attacks on her as an attempt to 'silence' the voices of black women.
Former Labor Senator Nova Peris sympathized saying she too knows 'what its like to be taken out of context' by powerful media outlets.
Larrakia actor and writer Jada Alberts said the 'reaction to her words is beyond ridiculous' and that the country is 'in desperate need of real leaders.'
Aria award-winning artist Briggs, from hip-hop duo A.B Original, showed his solidarity after he 'marched, raised his voice, and protested' with Ms Onus-Williams.
Speaking at the front of Parliament House on January 26, Ms Onus-Williams told the 60,000-strong crowd attending the Invasion Day rally in Melbourne, "We have not organised this to change the date. We have organised this to abolish Australia Day because f**ck Australia ... I hope it f**king burns to the ground."
Ms Onus-Williams says she has since faced a harsh backlash and racist taunts and reported that she believes someone had even attempted to hack her Twitter account.
"It's crazy how much racism and white supremacy has come out over my comment," she said.
"It just confirms why organisations or groups like WAR [Warriors of the Aboriginal Resistance] are so important to Aboriginal people in a country where we are silenced," she said.
"It speaks to why we need our grassroots movements, that are not funded by [the] government."
Conservative calls to get her fired
Upon hearing about Ms Onus-Williams'speech, former ALP President Warren Mundine called on political leaders to defund the stated-funded Koorie Youth Council, where Ms Onus-Williams is a volunteer.
Mr Mundine said her comments, and those of youth collective WAR, were an insult to all Australians.
"I support moving Australia Day to 1 January. But this lot says 'we don't want to celebrate Australia Day at all.' They're ashamed of Australia," he said on Linkedin.
But Mr Mundine, in-turn, faced criticism of his own after some Indigenous leaders slammed his comments.
Academic Marcia Langton said Mr Mundine's attack on the Koorie Youth Council 'crossed a line,' and Darkinjung Land Council CEO Sean Gordon was at a loss to explain Mr Mundine's comments.
In statement, the Koorie Youth Council distanced itself from Ms Onus-Williams. They confirmed they do 'not support her stance,' and that Friday's rally was 'separate from her volunteering at KYC.'
While Ms Onus-Williams says she fully "understands where they came from", she stood by her comments saying they were to be taken rhetorically, not literally.
"It was a metaphor, not actually a statement to be taken literally. I just want everything, all the governments to fall apart, because our people are dying and nobody cares and the whole system needs to change. The leaders of this country continue to ignore and oppress us. I am sick of our people getting locked up and dying in custody, of our young people suiciding,” she told Fairfax Media.
Dr Chelsea Bond, a senior lecturer at the University of Queensland, said Ms Onus-Williams 'has every right to be angry.'
In an IndigenousX article, Ms Bond said black women 'are not allowed to be angry, yet at the same time, we can never be cast as anything but the ‘angry black woman.’
"There is something particularly disturbing about campaigning to undermine an Indigenous youth organisation that she is affiliated with, simply because she had the audacity to be angry," she wrote.
While millions of Australians celebrated the landing of the First Fleet in 1788 on Friday, tens of thousands mobilised in capital cities to protest the date of January 26.
But WAR, the organisers of the largest Aboriginal rally staged since the 1970s land rights movement, dismissed the campaign to change the date of Australia Day as a "feel good" gesture that would do nothing to address fundamental issues of Aboriginal rights.