Layton's widow made the remarks following an advance screening of the film "Jack" at a Toronto theatre.
Friends and dignitaries in the audience included Layton's children Mike Layton and Sarah Layton, and 2011 federal campaign team members Brad Lavigne, Karl Belanger, Brian Topp and Anne McGrath.
"Jack" traces Chow and Layton's love affair, as well as his run through Toronto municipal politics, his emergence onto the national stage, the NDP's triumphant federal election campaign and his death from cancer just weeks later.
Rick Roberts stars as Layton, while CBC Radio personality Sook-Yin Lee plays Chow.
"Jack" premieres Sunday on CBC-TV. Special pre-screenings are also planned Tuesday in Ottawa and Thursday in Winnipeg, where the film was shot.
"Now, it's a movie, so Jack and I actually didn't kiss that much," Chow said to laughter as she took the microphone after the screening, which included a racy bedroom scene.
The federal MP noted that she's often asked why she gave her blessing to the film. She said she hopes it can inspire viewers to know they have the power to make a difference.
"Life is actually quite short and temporary," said Chow, joined at the front of the theatre by about 20 cast members, family and party faithful.
"If we can seize the moment and do as much and live as full a life as we can and make a difference (that's worth knowing). And we can make a difference ... So if we could get people to get a sense that: Yes, they can make a difference, yes they can live in a hopeful and loving way and change the world or change the community, change the neighbourhood, a little bit at a time. And that's worth the movie and all of us coming together."
Co-stars at the theatre included Wendy Crewson, who played McGrath; Zachary Bennett, who portrayed Lavigne; Joel Keller, who was Belanger and Judah Katz as Topp.
McGrath said she was so excited when she learned Crewson would play her, chuckling that "she's smarter and prettier than me but she did a fantastic job."
"One of the great things that I have liked about this whole process is how much respect I think there was between the producers and director and people that were working on it to talk to us and to find out how things were," said McGrath.
"To have been involved for the period of time that we had with Jack, to have had the privilege of working with him and with all of the people that he was able to inspire and bring around to him was a once in a lifetime opportunity.
"It was an awesome experience and what I love about this is that we get to relive it and remember it and it can sustain us to keep going."
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