The former Playboy Playmate announced her engagement to Hefner in December 2010 but later called off the marriage in June 2011 just days before the scheduled ceremony, citing a "change of heart".
Talking to Dr Drew Pinsky for Extra, Harris has since slammed accusations that she only became involved with Hefner for his money, insisting that she was not interested in the financial aspect of their relationship.
"If I was what people think I am, I would have stuck it out for another year. I was to get a gift of $800,000 (£486,000) the day after my wedding and $500,000 (£304,000) tax free every year after," the 25-year-old explained.
"I turned it down, walked away. I left because I realised money was not the most important thing in life."
Harris also said that she was "kind of broken" and "looking for a safe haven" upon meeting Hefner, due to abandonment issues stemming from the death of her father and childhood boyfriend, and claimed that Hefner made her feel like she was "somebody special" when he proposed to her.
Hefner has said that he "dodged a bullet" by not marrying Harris. He is currently dating Shera Bechard.