Like her husbands spectral visions, Lady Macbeth's sleepwalking seems to indicate guilt and a stricken conscience. Indeed, her ramblings during her sleepwalking episode demonstrates that by Act V, she is more affected by her husband's bloody rise to the throne than Macbeth himself. Imagining that her hands are covered in blood, she tries, to no avail, to scrub them clean. This, of course, is the famous "Out, damned spot!" speech, and it reveals that she is tormented by the murders committed in Macbeth's rise to power, and, one suspects, by her role in encouraging and planning the bloodshed. As the doctor observes after watching the disturbing scene:
Do breed unnatural troubles: infected minds
To their deaf pillows will discharge their secrets:
More needs she the divine than the physician.
Later, consumed by her guilt, Lady Macbeth commits suicide. She is a shell of the confident, ambitious, ruthless woman we see in Act I. Early in the play, she consciously makes herself into a monster in order to prod her husband to fulfill his destiny. By the play's final act, Macbeth is himself a murderous monster who no longer relies on his wife for motivation.