Final answer:
Lady Macbeth accuses Macbeth of cowardice and questions his love and manhood to coerce him into killing Duncan, implying that his reluctance is a sign of weakness.
Step-by-step explanation:
The evidence that supports the idea that Lady Macbeth believes her husband has decided not to kill the king because he is weak and cowardly is found in several lines she speaks. One piece of evidence is Lady Macbeth questioning Macbeth's courage and love, implying that his hesitance to proceed with the murder is a sign of weakness: “Was the hope dru.nk Wherein you dress’d yourself? hath it slept since? And wakes it now, to look so green and pale At what it did so freely?” She challenges his manhood saying, “Art thou afeard To be the same in thine own act and valour As thou art in desire?” Additionally, when Macbeth expresses doubts, Lady Macbeth pushes him further by asking, “What beast was 't then That made you break this enterprise to me? When you durst do it, then you were a man;” insinuating that his failure to act would make him less of a man.