The reason behind professional golfer Tiger Woods' mistress Rachel Uchitel leaving and returning to Celebrity Rehab has been revealed.

Uchitel had, as per a source close to her, left the Pasadena Recovery Center, where the show is taped, because "the demons from her past became too much to deal with".

And the reason she returned was because "she realized that she is part of a group and the group needs to know they can count on her for their sobriety".She did this [TV show] to show people who she is. She feels that then if they hate her, she's okay with that," People magazine quoted the source as saying.

"But she's not okay with them creating a character for her to play and represent. She's not the things people say. She wants a chance to prove that.

"She's trying to focus on what's going on there and take rehab seriously.

"It's very hard stuff dealing with past trauma. Being forced to look at it hurts," the source added.

A source close to the show said Uchitel wasn't gone long from the production.

"It was like she walked out and came back," the source said. (ANI)