Title: Putting up walls. Sentence 1: Benny was always moving house. Sentence 2: Because of this, he never made many friends in the neighbourhood. Sentence 3: He knew that if he made new friends, it would hurt when he left. Sentence 4: Benny has closed off so much that he doesn't have any friends now.
He felt he wasn't hurting others, but he was really hurting himself.