She was 23 and "not overly interested in politics"; he was 30 and already a National Party stalwart after years of working behind the scenes, including as Jim Bolger's secretary.
But Michelle insists her attitude changed as she got to know Todd and he taught her "the real side of politics".
"People have the perception that politicians are there for themselves, but they're not," she says. "Todd's passion and enthusiasm and desire to serve the community rubbed off on me."
Despite knowing political life was likely to be on the cards, the 38-year-old mother-of-three says the week since her husband's election has been surreal.
Speaking to Bay of Plenty Times Weekend at a Te Puna cafe, she says seeing her face on the front of the newspaper at the supermarket made her realise her family had lost their anonymity.
"I'm a very trusting and very open person. I'm probably going to have to be a bit more measured in what I say and do, but not lose my identity because first and foremost, I'm a mum and I'm a wife."
Friends joke that she will no longer be able to go down the road in track pants, but she hopes people will remember she is a mother and judge her accordingly.
"You might not always be on your finest form," she says.
We're equals in it. We've got really good communication. We are each other's rock.
The day of our interview, though, she is poised and chic in a floral blouse, jeans and boots. She arrives wearing a collared black jacket, but removes it for the photo, quipping that she is "not really a jacket person". Her posture is perfect, thanks to years spent as a competitive figure skater.
She describes herself as the "calming influence" to Todd's "hamster on a wheel", and says their marriage is "an absolute partnership".
"We're equals in it. We've got really good communication. We are each other's rock."
Faith is an important part of their bond, with Michelle trading in a "lukewarm Presbyterian" upbringing for Catholicism after meeting Todd.
His family church, St Joseph's in Te Puna, rallied her enthusiasm, thanks to a down-to-earth priest who hunted and fished, Maori songs, guitar players and even dogs at mass.
She was baptised when pregnant with their third child, Amelia, 6. Her elder two, Aimee, 10, and Bradley, 8, were baptised as infants and she followed suit in part to give consistency of message to her children.
Michelle is a full-time mum - "it's old fashioned, but it's what I enjoy" - and is focusing on resettling her children in Tauranga after several years back in Auckland for Todd's most recent job at Fonterra.
Born and raised in Auckland's Meadowbank, Michelle has a diploma in management from Auckland University of Technology and met Todd while working in marketing at Zespri.
They spied each other across the dance floor at the kiwifruit company's annual ball and quickly fell in love. Michelle had booked an OE and Todd, having recently returned from his overseas adventure, encouraged her to go.
"My trip away was about deciding whether I wanted to be the wife of an MP."
Her epiphany came while standing in the Sistine Chapel in Rome, and after six months away, she returned home and moved to Tauranga to be with Todd.
She hopes to get involved in charity work in the future and toys with the idea of retraining in a field such as psychology that involves helping people.
Although other partners of new MPs may be apprehensive about the impact of the job on their lives, Michelle hopes it will signal a more consistent routine for her family.
Todd's job at Fonterra involved lots of overseas travel, including long, unscheduled trips, and Michelle says several crises he endured at the dairy giant "thickened his skin" and prepared him for becoming an MP.
"This is his vocation, his calling," she says. "I'm totally behind him the whole way."
Michelle Muller is the first in a series of articles into 'The women behind our Bay MPs'.