We're sure Kristen Stewart has been making a lot of apologies lately, but she left one important person out of her public statement of remorse: her co-star and wife of Rupert Sanders, Liberty Ross.

“Kristen didn’t feel it was appropriate to issue a public apology to Liberty once the story of her affair with Rupert broke,” a source tells Radar Online. “Instead, she’s going to do the decent thing and write Liberty a private letter expressing her deepest regret for her actions."

A risky move, as Kristen may be the last person in the world that Liberty wants to hear from at this point, but sources say the Twilight star is overcome with guilt and desperately wants to make things right. "The fact that Liberty and Rupert have two kids has now dawned on her and she feels awful for what she did,” says the insider.

Well, at last that helps keep things in perspective. As much as Kristen may have messed up, at least she's not a middle-aged father of two. They both should've known better, but Rupert really should've known better.

(Photos: WENN)