The Busted star, 39, recently confessed his shame at "gaslighting" the 47-year-old Voice presenter — mother to his three children — when he was trying to hide his drink and drug addiction during their relationship.
But the couple came through their difficulties and portray a beautiful love story that has survived many challenges.
As Matt opens up on some of the darkest hours in a new BBC documentary — titled Matt Willis: Fighting Addiction — we look back at how their love blossomed from a chance encounter into the rock-solid relationship they have today.
Here's Matt Willis and Emma Willis's love story in 10 steps
Brought together by fate: Emma Griffiths began her TV presenting career on MTV interviewing bands and popstars.
In 2004 work required she interview Busted, she met Matt and a year later they were officially an item.
Imperfect proposal: When Matt took Emma to Venice for her birthday in 2007 she was unnerved by his silence and thought he was going to dump her. Then when he went down on one knee at a busy tourist spot she said "Don't you dare!"
But he did and she said 'yes'.
Crashed the wedding: Matt checked into rehab after Emma issued an ultimatum about his drink and drug uses ahead of their wedding. After rehab he found himself sucked into the Church of Scientology. But when they told him Emma was a "negative force" he saw the light and quit.
Perfect day: The pair said "I do" in 2008 at romantic Rushton Hall in Northamptonshire in a star-studded celebrity ceremony which featured in OK! Magazine. But Matt confessed he hates the wedding photos and never looks at them.
Little Brother: Emma welcomed their first child, daughter Isabelle in 2009, followed by son Ace in 2011. Emma has said Matt is the 'fun dad' and she is the 'boring one'.
Different career paths: Emma's career as a TV presenter really started to take off when she started hosting Big Brother in 2013 and then The Voice in 2014. Matt has dabbled in acting on TV and in the West End. They have since been reunited as a duo on Celebrity Gogglebox.
Growing family: The couple's third child Trixie was born in 2016.
Matt has said becoming a father changed his life for the better, making him realise he couldn't be a "naughty boy" anymore.
Relapse: Willis said in 2023 that he last relapsed five years ago. Part of the recovery process is to make amends to people he has hurt. But he admitted: “I never did that with Emma; I don’t think I ever can."
The Busted star has opened up on addiction in a new BBC documentary.
Wedding 2.0: In 2018 the couple renewed their vows to mark their 10th anniversary at their original venue, in a ceremony conducted by TV presenter Stephen Mulhern and a packed room of celebrity guests.
Now Matt can be proud of his wedding photos.
Watch: Why Matt Willis turned down Strictly
Matt Willis: Fighting Addiction airs on BBC One at 9pm on 16 May