How does the chapter "Notes" build on the previous chapter's theme of isolation and alienation?

Three years later O’Brien heard from Bowker’s mother. Bowker had hanged himself in the locker room of a YMCA, using a jump rope. His mother said she thought he did it that way because he was a quiet boy and “didn’t want to bother anyone” (158). O’Brien was shocked. This, however, is one example of the isolation and alienation soldiers felt after the war. The war didn't end for the soldiers during peace time. In many ways home was more traumatic psychologically than the war. Soldiers felt alone with the terrifying memories still in their heads.