He Loves Me (2011)

When Laura begins to suspect her husband is cheating on her, she is devastated by his infidelity, despite having a torrid affair of her own. While she desperately tries to save her marriage, Laura's mysterious past begins to emerge, making her more paranoid, delusional and violent in alarming ways. As her mental state continues to unravel, whoever gets in the way of Laura's myriad of fantasies becomes expendable, revealing the shocking dream world that insulates her from reality.