The 34-year-old was devastated when Sanders cheated on her with the 22-year-old actress, but after filing for divorce, she has decided to put the whole incident behind her, reported Contactmusic.
"The good thing about Liberty is that she's not upset anymore. She's had time to get over the initial shock and awe of it when it was exposed last year and the divorce was the nail in the coffin.
"That girl's extremely mature. She's handled all this public tragedy in her life with grace and humility for the sake of her children. I toast to her," a source said.
The actress's main priorities at the moment are her children, Sykla, seven, and Tennyson, five, and she is trying to get along with Sanders for their sake.
"All she cares about right now are her children and her future. She's spoken to Rupert by phone and the conversations were all business - trying to discuss the arrangements for the children," the source added.