Complex sentence: Instead of wallowing in self-pity and self-destruction like many of the expatriate members of the Lost Generation, Copland returned to America optimistic and enthusiastic about the future, determined to make his way as a full-time composer.
Split into simpler sentences: Instead of wallowing in self-pity and self-destruction like many of the expatriate members of the Lost Generation, Copland returned to America optimistic and enthusiastic about the future. On his return to the U.S., Copland determined to make his way as a full-time composer.