By Marissa Armas

DENVER (CBS4)– A childhood friend of a domestic violence victim in Denver is remembering her legacy after she was killed earlier this week. Andrew Bisset said he was friends with Katherine Pivoda, also known as Katy, for over 15 years.

Katy Pivoda (credit: Andrew Bisset)

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Pivoda was allegedly stabbed to death last Wednesday morning by her estranged husband Matthew Madden in a domestic violence attack. It happened at a home near the University of Denver, off of South Marion and Warren. Pivoda’s friend Jennifer Gelvin was also killed.

Bisset said he fell to knees when he heard the news.

“I asked her to prom because she was from outside the school, and we actually had to sneak… forge her principal’s signature on a permission slip,” Bisset said laughing. “I always knew that Katy possessed a wisdom and eloquence that was far beyond her years. She was the kind of friend that when I needed advice on major life decisions, I would contact her.”

Katy Pivoda (credit: Andrew Bisset)

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Bisset said Pivoda was kind and generous. She was also a mother of two and spent some time teaching in China. Bisset said she met Madden in China.

“We lost an exceptional person. We lost an exceptional person. I’m a lucky man to have known her at all. To have had her in my life for as long as I did. I consider myself exceptionally lucky,” said Bisset. “She was a gifted master of the English language, both by title, she did hold a masters, and just because she was incredible with words.”

Bisset said it’s the words that Pivoda left him with, those timeless memories that will keep him going as he mourns the loss of his friend.

Katy Pivoda (credit: Andrew Bisset)

“Katy was utterly unique and I think I knew that the minute I met her,” Bisset said. “There are some things that you can never replace and this is definitely one of them, and Katy can’t be replaced.”

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Pivoda’s friends and family have set up a GoFundMe page for her kids. Madden, 36, has been arrested in connection with the deadly stabbing deaths and is expected to make his first court appearance on Monday.

Marissa Armas