Joyce won a by-election last year to remain in Parliament after it emerged he was a New Zealand citizen.
Friends have reportedly told the Telegraph Joyce is said to be "madly in love".
But neither Joyce nor Campion have spoken publicly about their situation.
Before announcing his separation, the Deputy Prime Minister had frequently spoken about his wife and family in public.
In an interview with The Weekend Australian Magazine last year, his wife told the story of how the pair met.
The romantic encounter took place when they started studying at the University of New England.
"The first time we spoke was O Week," she said. "The last day was a car rally in a ute and he just came up to me and went 'You'll do'."
According to the profile, Joyce commented, "I had all the lines", and appeared "mortified".
In that same article the Nationals leader revealed how little time he spent at home with his family. His diary at the time showed only two days over the months of February and March that he would sleep at home in his own bed.
The Joyces have four daughters tougher — Bridgette, Julia, Caroline and Odette.
Mrs Joyce said at the time the family had taken a "back seat" to Mr Joyce's career. He entered politics when the youngest, Odette, was only 18 months.
"We're probably lucky, and not so lucky in a way, that (the children) were so young when he started so they don't really know any different," Mrs Joyce said.
"Every time he'd come home (Odette) actually wouldn't go near him because he hadn't been home. It's taken a long time to get that father-daughter rapport."
Joyce described feeling "guilt" over not always being there for his daughters.
"I hate it," he told the magazine. "In the end they give up on you. They just don't think you're going to be there."
Leading up to the New England by-election last year — after Joyce was dismissed from Parliament by the High Court over his dual citizen status with New Zealand — his wife and children did not accompany him on the campaign trail.
Joyce was also absent when her husband voted with his mother, and was nowhere to be seen when he was sworn back into Parliament.
By contrast, during the 2016 federal election, Joyce's family were frequently seen on the hustings.
His 2017 by-election campaign was dogged by rumours of the now exposed relationship.
During the campaign, Joyce was hounded by an individual, who he later dubbed a stalker, who raised his family situation at a pub sparking a heated verbal clash.
Joyce was understood to have knocked the man's hat off his had during the Monday night confrontation at a New England pub.
He acknowledged the rumours when he was reinstalled as an MP last year and confirmed his separation.
"I didn't come to this pretending to be a saint," he said.
