Brenda Doherty posted a moving tribute on Facebook to honour 82-year-old Ruth Burke, who on Monday became the fourth person to die in Northern Ireland after contracting COVID-19.
Ms Doherty said her mother "would not believe how people are behaving" as the government bids to enforce a nationwide lockdown to prevent the spread of the disease.
Police have been breaking up social gatherings and NHS workers have complained about facing packed London Underground trains on their way to hospitals.
Fighting back tears, Ms Doherty said: "To those of you who are out there being so selfish and gathering in crowds - wise up. How selfish can you be?"
And hitting out at people who have been panic buying at supermarkets, she added: "This is a time when people really need to think about others.
"I have a half a bottle of hand wash left because the shelves are empty.
"My mum would not believe how people are behaving. She would have thought better of society."
Chaotic scenes at supermarkets have been one of the headline features of the UK's coronavirus crisis, with healthcare workers among those unable to buy food as a result.
Last week, the top doctor at NHS England said panic buyers should "be ashamed".
Ms Doherty said her family would have to wait to properly celebrate her mother's life, with nobody having been allowed to see her when she passed away.
Funerals are one of the exceptions included in the lockdown announced by Boris Johnson on Monday night, but they have been restricted to immediate family members only.
Co-op Funeralcare director David Collingwood has said families still need to adhere to social distancing at a funeral, including remaining at least two metres apart.
Ms Doherty also paid tribute to the work of NHS staff who looked after her mother before she died.
"Mum was not just a statistic," she said.
"She was a woman who had unbelievable strength and suffered many challenges in her life.
"Unfortunately this was one that she wasn't going to overcome."
She added: "My mum was a woman who lived life to the full. She had lots of hard times in her life, but she valued life.
"If you value life, you will stay in and do as you've been asked."