Catherine O'Connor confessed to the killing of John Forrester, 42, the Irish Independent reported. Forrester and O'Connor lived in apartments in the same house in Bandon, County Cork.
O'Connor received a second life sentence, the Irish Examiner reported.
"We hope she'll never see the light of day again and be allowed to torture another family like she's tortured ours," Jamie Forrester, the victim's nephew, told the court.
Investigators said Forrester, a boat-maker from England, was killed in his flat and his body, secured with cables and wrapped in carpet, was dumped in the River Bandon. His feet were bound with the belt of O'Connor's sweater.
The body was discovered Nov. 15, 2011. O'Connor was convicted in July of the murder of Jonathan Duke, 27, whose body was also found in the river in November 2011.
O'Connor, who has three children, has been in custody since January 2012. Police said she first met Forrester several years ago while she was living on the streets of Cork.
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