The 77-year-old's son, who cannot be named because it could identify his mother, said the man accused of committing the crimes was a customer at his car yard.
The pair had celebrated together at his work Christmas party only weeks before the attack.
"He bought two cars from me, for him and his wife. Most of my customers are like my friends and family. As a customer I make everyone my friend. He was here every second Saturday after work for beers."
Police say the woman's attacker went in through the back door of her Papatoetoe home as she was about to collect laundry from outside.
The woman, who moved to New Zealand from Fiji 20 years ago and lives with her son and his wife, was left bruised and in shock following her ordeal.
But she had bounced back, her son said.
"When I saw my mum in the house like that, beaten and tied up, I was shocked.
"I took two weeks off work. I still tell her not to open the door.
"But she's been really good, now she is pretty happy. She's never scared to go out, she's a tough lady.
"She is praying every day that [her attacker] should be punished really badly. I tell her that he will be."
The man said the support from the Papatoetoe community had been immense, and he thanked the police for making an arrest.
