David has to come clean with Kathryn, but just can't in the end. Instead he tells her that he just can't connect with her since recovering from his coma, and that she should just go to Boston without him. When Kathryn goes crying to her friend, Regina, she finds out that there's more to it than that. Kathryn finally finds out about the affair thanks to some scandalous photos and she's livid. She confronts Mary Margaret at the school and MM finds out that David lied to her about telling Kathryn the truth. And to make things worse, the entire town seems to have turned on her for finding love with a married man. Someone even spray paints "tramp" on Mary Margaret's car. In the end, she can't stay with David—his lying hurt her too much.