“you’re two-timing me with Cervantes.”

 It was a measure of that devotion that one day, while she was immersed in translating “Don Quixote,” the phone rang. It was Mr. García Márquez, sounding like a jealous husband. “I hear,” he said, “you’re two-timing me with Cervantes.”

Meaning of two-timing in Englishto deceive someone you are having a relationship with by having a secret sexual relationship with someone else at the same time: I ended the relationship when I found out he was two-timing me.