Thomas Meagher was struggling to cope with the disappearance of his wife of four years, his mother said in Dublin yesterday.
Speaking before the arrest of a 41-year-old Coburg man in connection with Jill Meagher's disappearance, Joan Meagher said her son was heartbroken.
"He's not doing well at all actually. I don't think he's coping," she told the Irish Daily Mail.
"Tom is coming off far better on the TV right now than he is in reality.
Her daughter Katrina, who was a bridesmaid at Thomas and Jillian's wedding in 2008, has flown from Ireland to Melbourne to support her brother.
Mrs Meagher said it was heartbreaking being so far from her son.
"I only know what's happening from the internet. She's gone and we want her back. We are just devastated for Tom," she said.
The couple met at University College Dublin about 10 years ago and travelled the world together before settling in Melbourne in 2009.
Friends from across Ireland and Australia continued to post messages of support on Mr Meagher's Facebook page yesterday.
Ms Meagher's parents Edith and George remain in Perth because her father is too unwell to travel after a recent stroke.
Her brother Michael McKeon flew to Melbourne earlier this week.
Ms Meagher's uncle Michael McKeon, who lives in Ireland, told the Irish Independent that the family was living through a nightmare.
"It's an unreal nightmare," he said. "It's mind-numbing in many ways, your thought process kind of shuts down.
"It's the helplessness of the situation. They're looking for her but, to an extent, they've done all they can do."
He recalled seeing his niece just weeks ago when she visited Ireland before cutting her holiday short after her father's stroke.
"It's hard to fathom that Jill was at home in Ireland and we had a night out with her just three weeks ago," he said.
One of Ms Meagher's cousins, Richie Burke, spoke out against the initial speculation surrounding Mr Meagher.
"People just have negative thoughts and that is always going to be on social networks," he said.
"It is purely run-of-the-mill that the police question the husband in a case like this, but we are all supporting him."
He said his mother, Marie Burke, was on the phone daily to her youngest sister in Perth.
"Mam and her sister would always Skype one another, but they have had to go back to phones as it is too hard looking into each other's faces," Mr Burke said.
"There were too many tears and emotions - it was just too painful for everyone."