Silver Linings Playbook ending explained (spoilers)

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Pat and Tiffany score horribly on the dance competition, but it doesn't matter because their lousy score was enough to win the Eagles bet. Nikki comes to the competition, much to Tiffany's surprise, and as Pat goes to talk to her, Tiffany storms out. Pat whispers something in Nikki's ear and they part on good terms. Pat catches up to Tiffany and gives her a letter he wrote to her. The letter says that Pat knew Tiffany wrote Nikki's letter, but Pat doesn't care and that he loves her. They kiss.