Lisa Moller, 35 was found hanged at home in Barry, Vale of Glamorgan, in August after a row with her boyfriend.
Recording a narrative conclusion, the coroner said she had deliberately caused her own death, but her intentions were unclear.
He added that the police had had no right to enter her home.
An investigation by the Independent Police Complaints Commission is ongoing.
Police were called to the house Ms Moller shared with Joseph Ashenhurst in Cwrt Eirlys in the early hours of 31 August after reports of screaming and shouting.
Officers took him to the police station and Ms Moller was left in the house alone.
Det Sgt Anthony Evans said after Mr Ashenhurst left, officers called at the house at 02:00 BST and 04:24 and also called her mobile phone, but failed to make contact with her.
He said the officers did not attempt to force their way into the property because they were "mindful of the law" and there was nothing to indicate Ms Moller might self harm.
Mr Ashenhurst returned to the house after being questioned by the police and slept in the car.
He said he broke into the house at about 10:50 and found Ms Moller.
Assistant coroner for Cardiff and the Vale Christopher Woolley said it was clear she had suffered verbal abuse in the hours before her death, but there was nothing in her medical history to indicate significant depression or attempts to self harm.
He said the police could only have forced entry to the house if they had evidence of the potential for Ms Moller to self harm.
There was no neglect by police in the case of a woman who was found dead at her home hours after officers tried to check on her, a coroner has said.