Complex sentence: Gentlemanly yet indecisive, he loves Scarlett, but finds he has more in common with Melanie, his cousin and later his wife, but is tormented by his obsession with Scarlett.
Split into simpler sentences: Gentlemanly yet indecisive, he loves Scarlett, but finds he has more in common with Melanie, his cousin and later his wife. But he is tormented by his obsession with Scarlett.