Complex sentence: Lucas told Sami that he was ashamed of the man he used to be, the one that had loved her and left her in the past and because of that Sami was afraid to come and tell him when EJ started threatening her.
Split into simpler sentences: Lucas told Sami that he was ashamed of the man he used to be, the one that had loved her and left her in the past. And because of that Sami was afraid to come and tell him when EJ started threatening her.