"It was not very nice. This was 10 years ago, it was pretty rough," she said about the experience.
"I've grown from that experience and I'm much better at living life on the right side of the law now."
Originally from Matamata, Mary used to go by the name Robert Haddock, and was once accused of stalking newsreader Simon Dallow.
In a candid interview with Third Degree's Paula Penfold last year, she denied ever stalking the presenter but admitted she did send malicious emails about him.
She said: "I was an attention seeker. I was someone that was trying to be someone that I wasn't."
Haddock-Staniland says she is a little bit scared heading into the Ladies of New Zealand house, which will see four women from around New Zealand live together for a week, while being filmed by ZM cameras.
"I'm me being me and I'm happy as me," she said. "There really is something about Mary."
ZM Content Director Sarah Gandy said there was a wide variety of applicants for the competition but Haddock-Staniland instantly stood out.
"Our aim is to showcase the incredible range of ladies living in New Zealand. We were struck by Mary's honesty, enthusiasm and of course her fabulous sense of self. We hope others will find her as inspiring as we do".
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