The 18-year-old, who finished fourth in the series, blamed abuse from some viewers on her putting up a wall to stop people from getting to her.
"I was overwhelmed by the amount of interest in me. So I was a bitch, a real bitch. Knowing what I know now, I would've dealt with situations a lot more calmer," Cher tells heat magazine this week.
She continues: "I was just so angry and frustrated that people had taken my life off or me, even though I had gone on the show."
The 'Swagger Jagger' hitmaker, who was mentored by Cheryl Cole on the series, said taking part in the competition was "mayhem".
She explained: "What did I go through? Absolute stress and mayhem. I couldn't go out, because people were constantly on my back all the time. I just felt like I was doing something I loved, but there was another part of it that I absolutely hated.
"I didn't know who I was, people took that away from me."