Darren Jones, of Colwyn Bay, was investigated in connection with possible manslaughter charges after leaving Delyth Morwen Jones on steps leading to the beach at Colwyn Bay, last September.
He admitted to police that had he made an effort to bring her off the beach she would have lived. He told an inquest in Llandudno yesterday, ``I shouldn't have walked away from her.''
The following day her body was found in the sea at Colwyn Bay.
The inquest in Llandudno heard that Miss Jones, 23, from Llanrwst, had been friends with Mr Jones since their school days.
Mr Jones had been living with Delyth's brother in a flat in Colwyn Bay. He and Miss Jones often went to the beach for a drink before returning to Mr Trefor Jones's flat.
The inquest later heard that to avoid paying the rent, Mr Jones had lied to his flatmate that his mother had died.
Further Miss Jones only went to the flat because she believed the lie and wanted to comfort Darren.
Miss Jones death was caused by drowning, which was due to her drunken state, the inquest was told. An open verdict was returned.