Ashley Ruscoe, 35, was arrested and taken to Waverley police station on Wednesday night, when she was charged with domestic violence-related offences.
NSW Police said the charges stemmed from an investigation in an alleged domestic violence incident at a Bellevue Hill home, in Sydney's east, on March 1.
Police say they arrested a 35-year-old woman at the home about 4.45pm on Wednesday.
"She was taken to Waverley police station and charged with common assault (DV) and stalk/intimidate with the intention to cause fear of physical harm," NSW Police said in a statement.
Ruscoe will face Downing Centre Local Court on July 19.
The arrest is the latest development in a long-running saga involving the estranged couple.
Garside was arrested on May 2 at Sydney Airport and charged with domestic violence-related common assault over the same March 1 incident.
The charge and apprehended violence order application against the 25-year-old boxer were formally withdrawn in June.
According to Garside, his lawyers provided "recordings and communications" to police which showed a different version of events and cleared him of any wrongdoing.
He previously said the ordeal has been devastating as he returned to Australia from filming a reality TV series and prepared to qualify for the 2024 Paris Olympics.
"What has occurred ... has been personally devastating and a real test of my resilience," Garside said.
"I will be forever grateful for the love and support of my family and friends who have kept me strong and focused."
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