A vulnerable elderly woman was "brainwashed" by scammers who stole £20,000 from her before she died.
Elaine Chamberlain, 76, believed she was going to marry one of scammers after meeting him online in 2019.
Her son Richard Chamberlain, 53, said she even bought a wedding dress and marital rings, adding that the scammers "ruined" his mother's life and "stole her dignity".
The retail manager from Sheffield said: "These people were in her head. They knew what they were doing, they made her feel special, they made her feel wanted and good about herself.
"It didn't matter what anyone said to her."
RIchard said his mother, who had arthritis, started deteriorating following the death of her partner of 31 years, Danny, in 2013.
He added: “When he died, Mum was lost, he was the love of her life."
The first sign of trouble came in 2019 when Elaine said she had met a man online but became "vague" when Richard asked about him, he said.
Richard added: "I knew scammers were about, so I said to her, 'You're sending him money are you?' and she said that she wasn’t."
Elaine, a former dinner lady from Sheffield, was led to believe the person she was talking to was a white man in his 60s, working abroad as a diver on a ship.
However, Richard carried out online research and established that the image being shown to Elaine had been taken from a Welsh man's Facebook profile.
His worries were confirmed a short time later when Elaine answered her phone on loud-speaker and Richard heard a young man's voice on the other end.
He said: "You could tell from the voice that it wasn't the man in the picture. I told Mum, 'You’re being scammed,' but she would just say, 'No I'm not, no I'm not.'"
In early 2020, the Post Office where Elaine deposited the £20,000 in cash contacted South Yorkshire Police about unusual activity from her account and officers went to see her.
According to Richard, they told her that what she was doing was wrong and advised her to stop.
He also notified social services and his mother's bank.
However, he said she got around this by visiting money exchange centres instead of Post Offices.
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Within weeks, Richard had found receipts showing his mother had been asked to send money to UK addresses in Leeds and London.
He claims to have told police and urged them to investigate, but said he was told his mother had chosen to send the money, so there was nothing they could do.
"By that point, my mum was brainwashed," he said.
Richard said he had to remove himself from the situation for mental health reasons and that he didn’t speak to his mother for a few months.
When they got back in touch at the end of 2020, he said: "Mum was in really poor health and the house was in a terrible state.
"All she was interested in was this man, she was constantly online talking to him.
"I was looking at my mum and it was like looking at a blank page, all these people had to do was click their fingers and she would do anything."
Richard said his mother was eventually rushed to hospital with cellulitis, and within hours that she had died from multiple organ failure.
He then discovered she had died with only £120 to her name.
Richard also later found a wedding dress and two rings in her bedroom, adding that she had sent pictures of herself wearing the dress to the scammers.
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