Complex sentence: Thinking that all hope of having a happy life with Susan and Stephanie has been ruined, Jerry quits his job and creates a new identity for himself in another town, where he begins to court another widow while planning to get rid of Susan and Stephanie.
Split into simpler sentences: Thinking that all hope of having a happy life with Susan and Stephanie has been ruined, Jerry quits his job and creates a new identity for himself in another town. He begins to court another widow, while planning to get rid of Susan and Stephanie.