Cheyenne had told authorities that she and her friend had been out drinking and got into an argument, but that she couldn’t remember strangling Brittney on the night of her death. She also claimed her friend had gone home with an unnamed man that evening, The Sun reports.
But after examination of the selfie and by piecing a together a timeline from other social media pictures, police charged the 21-year-old with second-degree murder.
Cheyenne has now taken responsibility for Britney's death—although she says she does not remember killing her—and plead guilty to the lesser charge of manslaughter. She was sentenced to seven years in jail on Monday.
“I will never forgive myself. Nothing I say or do will ever bring her back,” Cheyenne said in a statement issued through her lawyer.
“I am very, very sorry ... It shouldn’t have ever happened.”