AceShowbiz - Sandra Bullock's troubled marriage has been rocked by new reports her husband Jesse James had an affair with a fourth woman behind her back. The Hollywood star walked out on James in early march after tattoo model Michelle McGee went public with claims she romanced the married reality TV star for 11 months - including a period when Bullock was shooting "The Blind Side" on location.

A second woman came forward last week with fresh allegations of infidelity leveled at James and a third woman, who initially made claims, has since retracted her comments, insisting she was never intimate with the TV mechanic.

Now it has emerged there's a fourth potential mistress - but she intends to keep her alleged affair with James private. The unnamed woman has hired top lawyer Gloria Allred to protect her privacy from the tabloids. Allred, who currently represents two of the women involved in the Tiger Woods cheating scandal, confirmed last week she had been appointed to represent the woman, described as a "beautiful model and businesswoman". In a brief statement issued on Monday, March 29, Allred says, "I can confirm that she has decided not to tell her story. I have no other comment."

Bullock moved out of the home she shared with James in Long Beach, California shortly after news of the McGee affair broke in early March. She is said to be staying at her property in the Hollywood Hills.