Bert constantly questions his girlfriend about her whereabouts. He gets extremely anxious and overbearing when he is unable to track her. Bert's therapist tells him that he understands that Bert is afraid of losing his girlfriend as he loves her a lot; he further tries to rationalize that Bert's overbearing nature will eventually cause his girlfriend to leave him, which makes Bert anxious. In this scenario, Bert's therapist is using ________ to treat him.