In May 2007, whilst Ashley and Joshua visit Maxine's parents, the Peacocks' house is set on fire. Claire is rescued but Freddie is missing and is later found in a local park. Claire suspects her former friend Casey Carswell (Zoe Henry) but Ashley does not believe her. One day whilst Claire is out, Ashley kisses Casey and they agree to forget it ever happened. However, Casey has no intention of forgetting anything, manipulating Ashley into having an affair. They are almost caught when Claire returns from a trauma support group. Feeling guilty about his affair, Ashley tells Audrey and Kevin Webster (Michael Le Vell). Ashley decides to make his marriage work and ends things with Casey but, adamant that Ashley loves her, Casey pesters him constantly. Claire becomes suspicious, as Casey had stayed with Ashley while she was away, and she asks Ashley if he had slept with Casey but he denies it. Casey becomes obsessed with Ashley and is prepared to do anything to get his attention, eventually kidnapping Freddie and takes him to her house, knowing Ashley would come to get him. When Ashley arrives, he is horrified to see Casey has photos of him everywhere. He tries to reason with her but Claire barges in and Audrey, who also accompanied them, calls the police. Claire talks to Casey and she reveals her affair with Ashley. Claire rescues Freddie, and Casey is arrested and admits starting the fire at the Peacocks' house. After Ashley and Casey's affair is revealed, Claire tells Ashley that their marriage is over. He moves out, staying briefly with the Websters before moving in with Audrey, Bill Webster (Peter Armitage) and her grandson, David Platt (Jack P. Shepherd). Ashley sees Joshua and Freddie regularly but it is clear that Claire is angry and hurt by his actions. She struggles with childcare and work but cannot bring herself to forgive Ashley until Audrey convinces her to do so and the couple reconcile.