Meet the single mum who just won the biggest lottery in human history.

On Wednesday night, 53-year-old Mavis Wanczyk was leaving Mercy Medical Centre in Springfield, Massachusetts, a hospital where she had held a job for the past 32 years.

As she prepared to walk out, the winning numbers for the US$759 million (AU$964 million) Powerball had just been announced and her workmate, Rob, was reading them out to her.

That’s when the mum-of-two realised she had just won the biggest lottery in US history.

“He’s reading these numbers, and I pull mine out, and I go, ‘Hey, I have that number, and I have that, I have that!’”, she told a press conference in Massachusetts.

“And he goes, ‘Let me see that ticket'”. Seconds later, he was screaming, “You just won!”

In the minutes that followed, Wanczyk says, “I couldn’t drive anywhere. I couldn’t do anything. He followed me to make sure I was safely home.”

At first, the patient care worker couldn’t believe her luck, but now she’s quit her job and is planning her early retirement.

“I have called them and told them I will not be coming back. I just want to sit back and relax,” she said, adding, “I had a pipe dream, and my pipe dream has finally come true, I wanted to retire and it came early.”

The win is bittersweet for Wanczyk whose ex-husband, William, was killed in a hit and run accident last November.

William was waiting at a bus shelter in Northampton, Massachusetts when an out-of-control driver smashed into the shelter, killing him instantly and then fleeing the scene.

The driver, 20-year-old Peter Sheremeta, wasn’t identified and charged until just a few months ago.

Wanczyk has a 31-year-old daughter and a 26-year-old son, and in the immediate future, she plans to pay off her car and spend some time thinking about what she wants to do with the money.

“I just want to be me. Be alone and figure out what I want to do.”

What would you do if you won the lottery? 

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