what had perry realized about the Clutter murders-they came to symbolize what to Perry?

I think in the end the Clutters symbolize everything that Perry did not have. The very functional Clutter family reminds Perry of all that he resents in his own past. Ultimately, however, his righteous and well-to-do lifestyle plays him into the hands of his killers (like Perry), who make him first the target of their attempted robbery and, later, a scapegoat for their own resentments.