Answer:
That she is a snob is the way in which Oedipus interprets Jocasta's sudden exit in "Oedipus Rex" by Sophocles (495 B.C.E. - 405 B.C.E.).
Specifically, Theban King Oedipus discovers that he is the adopted or biological son of his presumed parents, Corinthian monarchs Polybus and Merope. He then finds out that his birthplace is within the Theban not the Corinthian royal household. Oedipus observes that his presumed humble birth to a palace servant offends his wife Queen Jocasta, who undoubtedly leaves because she likes to put on airs about her noble and royal ancestry.