The Dilemma

2011 Dramedy about a man named Ronny (Vince Vaughn) who sees the wife (Winona Ryder) of his best friend Nick (Kevin James) cheating with another man. Ronny then goes through great pains to collect proof, while hiding the information until the right time. Directed by Ron Howard.

Tropes associated with this movie:

 * Blackmail: Geneva does this to Ronny.
 * Completely Different Title: The German for dilemma is "dilemma". So naturally in Germany The Dilemma is shown as Dickste Freunde -- which means Fat Friends. Or less literally Best Friends.
 * Manipulative Bitch: Geneva.
 * Mood Whiplash
 * Never Trust a Trailer: This film was advertised as a laugh-out-loud comedy. It does have some hilarious moments, but for the most part, the film is quite dark.
 * Relative Error: Ronny mistakes a man talking to his girlfriend as trying to feel her up but when he confronts them Ronny's girlfriend says that the man is her cousin. And gay.
 * Took a Level In Badass: Ronny creates a flamethrower using a candle and cleaning solution to scare off the man Geneva's seeing.
 * Ugly Guy, Hot Wife: Vince Vaughn and Kevin James are average-looking at best, and both are quite overweight (the latter more so) -- but snagged women who look like Jennifer Connelly and Winona Ryder. A New York Times review pointed out the absurdity of this.
 * Your Cheating Heart: Basically the whole premise of the movie.