As a result of information received, it was found Mahara had started living in a relationship with Cole in August 1990.
Between October 1995 and September 2011, Mahara filled out 16 documents in which she stated she was not living with a person in a relationship in the nature of a marriage and/or was single.
Between March 1997 and June 2011, Mahara filled out seven forms on which she provided a false address or incomplete information on who she lived with.
On two occasions she provided Cole with letters to support him getting a domestic purposes benefit.
The court was previously told that Mahara was repaying the money.
Mahara's lawyer, Douglas Hall, said Mahara was remorseful and her offending was not a case of greed but of need.
"She was struggling to get by."
Cole had been absent for long periods of time and Mahara has four children, one of whom suffered from rheumatic fever. Mahara had done her best to support her family and there was no steady cashflow.
She acknowledged that what she had done was wrong and said she would not get involved in this type of offending again.
Ms Cohen said she rejected that there was not a steady cashflow. She said Mahara and Cole, who is due to be sentenced on December 12, were overpaid more than $300,000 between them.
Judge Peter Spiller said the starting point was three years' jail but he reduced that to two years to give her credit for her guilty plea and remorse.
Judge Spiller said he would convert the two years' jail to 12 months' home detention and also sentenced her to 150 hours' community work.