The former 'Dancing With The Stars' contestant told 'Entertainment Tonight' on Monday: "Both of us were married. We did not have an affair. But again, I think what I did was worse. Because I think when you fall in love with someone when you're married you jeopardise your own marriage and their marriage. It's doubly bad."
Kristie insisted she is good friends with Patrick's wife of 34 years Lisa Niemi Swayze and was even asked to speak at his funeral after he died of pancreatic cancer in 2009.
The actress's latest revelation comes just days after she admitted she fell head over heels in love with John Travolta on the set of their Christmas movie almost 25 years ago but couldn't act on her feelings because she was married to actor Parker Stevenson at the time.
She said: "Believe me, it took everything that I had, inside, outside, whatever, to not run off and marry John. And be with John for the rest of my life. [He was the] greatest love of my life."
John, 58 - who is married to Kelly Preston - was single when they met and when Kirstie was asked why she didn't leave her husband for her co-star, she insisted the institution of marriage was very important to her.