What does the doth protest to much mean?

Answer 1

This is a misquotation of Gertude's line in Hamlet, "The lady doth protest too much, methinks." She is watching a play in which a woman swears up and down she will never remarry and does so immediately on her husband's death. The line is ironic since Gertrude herself did exactly what the woman in the play did. The line has come to be quoted (or as often or not, misquoted) to describe someone who is a little too insistent, and so is not believable.