Date: Not recent. I guess 1990-2010.
Country of origin: Probably the U.S.
Two men sitting next to each other on a flight, begin a conversation.
They become friendly and MAN-A says, that if his wife would cheat on him, he would kill that guy.
The plane lands, they part ways.
MAN-B (who is also married) meets a woman in a bar and eventually has a one-night stand with her. She wore a red dress.
Some time later MAN-B runs into MAN-A with the woman from the bar on his arm, she turns out to be MAN-A's wife.
No more info, except that it ends in an airport.