Silip (2007)

Small-town waitress Tess is swept off her feet by dashing salesman Rico, who marries her and takes her to live on his isolated farm. When Rico goes on a sales trip and leaves her all alone, Tess fights off loneliness by befriending Celia. Suspicions that Celia may be having an affair with her husband soon creep into Tess's mind and threaten her sanity.