Complex sentence: He discovers that he and Mrs. Robinson have nothing to talk about and that she only wants sex, however after pestering her one evening, Mrs. Robinson reveals that she is in a loveless marriage because she errantly became pregnant with her daughter, Elaine.
Split into simpler sentences: He discovers that he and Mrs. Robinson have nothing to talk about and that she only wants sex. However, after Benjamin pesters her one evening, Mrs. Robinson reveals that she is in a loveless marriage because she errantly became pregnant with her daughter, Elaine.