Complex sentence: After this pattern has been established, Nick (Cariou) leaves his wife Anne (Dennis) for a much younger Ginny (Armstrong) and brings her on their shared vacations, causing the other two couples to be uncomfortable with the situation.
Split into simpler sentences: After this pattern has been established, Nick (Cariou) leaves his wife Anne (Dennis) for a much younger women, Ginny (Armstrong). Nick then brings Ginny on the couples' shared vacations, causing the other two couples to be uncomfortable with the situation.