A birthday card that Brad Pitt sent to Jennifer Aniston for her 38th birthday on Feb. 11, flipped Angelina Jolie out completely. The problem wasn't the fact that Pitt reached out to his ex. It was the fact that he signed the card "with love, Brad" and he did do during a period when Jolie was feeling extremely vulnerable following the loss of her mother Marcheline Bertrand to ovarian cancer on Jan. 27.

"It was an affectionate gesture on his part, and he sees no reason not to reach out and extend an olive branch," a source tells Star. Ironically, the final indiscretion on Pitt's part was his decision to tell Jolie about the card. That was when a deeply saddened Jolie "hit the roof!" the source says.

"Brad saw nothing wrong with his behavior. He said, 'You should never burn bridges,' and reminded her that he and Jen may have no future together, but they could still be friends." But, says the source, "Angelina is unsteady and none of this went down well."

Pitt usually defers to Jolie's emotional state. For example on Jan. 22, shortly before Bertrand's death, while filming The Curious Case of Benjamin Button he declined to kiss ravishing co-star Megan Brown. "Brad looked at her and said, 'Nah, I don't think so!'" says an on-set source. When Star questioned Brown about the interrupted love scene, Brown simply said, "No comment."