Lady Macbeth sees a bloodstain on her hands because she?

Lady Macbeth sees bloodstains on her hands because of her part in the murders of Lady Macduff and Banquo. She may not have taken part in the direct murders, but she was compliant and encouraged her husband's ambition. She even went so far as to shame him for his own lack of ambition. The bloodstains she sees upon her hands serve as a symbol of guilt.