The ex-wife of former Billabong boss Matthew Perrin broke down as she described how he confessed to losing their "forever home".
He used the family's custom-built property on Cronin Island, Surfers Paradise, as security for $13.5 million credit from the Commonwealth Bank.
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Perrin did 'bad things'
Former Billabong CEO Matthew Perrin faces court on 12 counts forgery and fraud after writing his wife's signature on loan documents. Nine News
The former CEO of the surfwear company allegedly forged his wife-at-the-time's signature on the mortgage documents.
Mr Perrin called the family together after his investments went wrong and allegedly made the shocking confession: "I'm going to jail, I've done a lot of bad things."
His ex-wife Nicole Bricknell said he had previously promised her that the house was in her name and was safe after she discovered he had been having an affair.
She initially thought he was going to admit he had been unfaithful again but he replied "it's much worse than that".
The trial at the District Court in Brisbane had to be halted when she broke down in tears and began hyperventilating during her evidence.
The couple had designed and built the $15 million property together as a "forever home" for them and their three children, Ms Bricknell said.
![Matthew Perrin allegedly forged his wife's signature on mortgage documents.](/web/20161213094320im_/http://www.theage.com.au/content/dam/images/g/t/9/a/d/i/image.related.articleLeadwide.620x349.gt9xkl.png/1481604916775.jpg)
Mr Perrin admits signing his former wife's name but claims he had her permission to do so.
She insists that she had no idea what he was doing and never gave him authority to sign on her behalf.
Ms Bricknell was formerly a beautician before quitting work to stay at home and look after their children.
She said she looked after the household and her husband dealt with all their finances.
Mr Perrin is also accused of faking his brother's signature as a witness on the paperwork.
Fraser Perrin was shown the documents in court and confirmed that he had never signed them.
The defendant denies nine charges of forgery and three of fraud in 2008.
AAP