Operation the Lion Sleeps Tonight (or the Cheater, Bastard and Coward) (смешанная)

Have you been so busy that you've forgotten what time of year it is? Let me give you a hint. Couture, quadrilles, and cutthroat competition. That's right. It's time for Cotillion.
-Gossip Girl
Prompt: My boyfriend cheated on me with another girl. instead of fighting over him, we got together.