Kristen Stewart Writes Letter to Director's Wife, Seeking Forgiveness After Affair (PHOTO)

Kristen Stewart was recently criticized for failing to mention Rupert Sanders' wife in her public apology for engaging in an affair and cheating on her boyfriend Rob Pattinson, but new reports suggest that the actress is writing a private letter to apologize directly to her.

The 22-year-old will ask for forgiveness in her letter to Sanders' wife and the mother of his two children, Liberty Ross, after admitting to having an affair with the 34-year-old's director husband.

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

"She was thinking of including Liberty, Rupert and the kids in her public apology – but Kristen was so desperate to save her relationship with Rob she decided to concentrate on that first. Kristen feels she made a terribly naive mistake and will do anything to make amends. The fact that Liberty and Rupert have two kids has now dawned on her and she feels awful for what she did," the source added.

Stewart was photographed intimately hugging and kissing 41-year-old Sanders, who directed her latest film "Snow White and the Huntsman," which led to speculation that the pair was having an affair.

Stewart, who has been dating Pattinson for three years, almost immediately confessed to cheating with Sanders after the intimate photos went viral.

"I'm deeply sorry for the hurt and embarrassment I've caused to those close to me and everyone this has affected. This momentary indiscretion has jeopardized the most important thing in my life, the person I love and respect the most, Rob. I love him, I love him, I'm so sorry," Stewart said in a public statement.

Pattinson, 26, is yet to publicly respond to Stewart's cheating admission because he is said to be "in shock" over the situation and confused as to what to do.

"Rob is in shock that Kristen cheated on him, he is absolutely devastated. But right now he doesn't want to say anything in public until he figures out what he's going to do," a source close to the actor told Radar

Meanwhile Sanders, who has received far less criticism than Stewart over the affair, spoke out and apologized directly to his family.

"I am utterly distraught about the pain I have caused my family. My beautiful wife and heavenly children are all I have in this world. I love them with all my heart. I am praying that we can get through this together," Sanders said in a statement to Reuters.

(PHOTO: Kristen Stewart) Twitter: @OyeMexicoKristen Stewart and Rob Pattinson (L). Rupert Sanders and wife Liberty Ross (R). Kristen Stewart and Rupert Sanders (Center)