A Facebook post recently turned into a nightmare for a Canadian woman. The woman, who killed her friend, avoided the clutches of law for two years until the police saw her Facebook selfie with her friend. Cheyenne Rose Antoine, 21, pleaded guilty earlier this week to killing her 'friend' Brittney Gargol, 18. However, Antoine's Facebook post became instrumental in the investigation and got her a seven-year prison sentence. The case got solved when the police discovered the weapon - a belt, used in a picture of the pair posted just hours before the incident. Gargol\u2019s body was found near a landfill in Saskatoon two years ago \u2013 she had been strangled to death. Antoine had till now, maintained that some friends had been out drinking on the night of Gargol's death and got into an argument but she doesn\u2019t remember killing her friend. Antoine was initially charged with second-degree murder, but she later pleaded guilty to manslaughter. Later, she was identified as a suspect after she posted a selfie on Facebook of the two of them, showing her wearing the belt hours before Gargol died. Before the murder, the two friends were considered 'inseparable', as per media reports. The twist in the story came when Gargol was discovered dead on a road by a passerby in the early morning of 25 March 2014. Police said that no evidence could be found to verify the story Antoine first gave to them - which was that the pair had gone from a house party to some bars before Gargol left with an unidentified man, while Antoine went to see her uncle. Police soon realised that Antoine's Facebook post on Gargol's personal page the following morning - "Where are you? Haven't heard from you. Hope you made it home safe" - was a diversion. She had also asked her uncle to provide a false alibi. Antoine now says the pair were drunk and high on marijuana when they got into a heated argument. She accepts she was responsible for strangling her best friend - although she says she doesn't actually remember the events. "I will never forgive myself. Nothing I say or do will ever bring her back. I am very, very sorry. It shouldn't have ever happened," she said in a statement through her lawyer.