Final answer:
Lady Macbeth initially reacts to Duncan's murder without guilt, focusing on managing the situation and instructing Macbeth to wash the blood from his hands to conceal their crime. She demonstrates fear and ambition, but as the play progresses, her guilt becomes evident through her disturbed behavior.
Step-by-step explanation:
Lady Macbeth's reaction to Duncan's murder is a complex blend of practicality, fear, and ambition. Initially, she does not express guilt or regret; rather, she is concerned with managing the situation and the consequences of the act. When Macbeth is overwhelmed by the enormity of the murder, Lady Macbeth tells him to wash the blood off his hands and chastises him for bringing the daggers from the murder scene, urging him to return them and smear the grooms with blood.
Her reaction is pragmatic, aiming to conceal their guilt and maintain their facade of innocence. As Macbeth becomes increasingly consumed by guilt, it is Lady Macbeth who attempts to strengthen him, criticizing his fear and weakness, and reminding him of the need for courage.
Later in the play, however, she is haunted by the murder, ultimately suggesting an internal conflict and the emergence of deep-seated guilt, as evidenced by her sleepwalking and obsessive hand-washing.