In act 5, scene 1, 24-42, what theme would be most necessary for this situation?

In Act 5, Scene 1, 24-42 of Macbeth, one of the most apt themes would be guilt. Lady Macbeth is sleepwalking, which she does every night. As she walks, she tries to wash the symbolic blood from her hands. This blood represents all the people that she and Macbeth have had removed from their ambitious path. This activity is noted by the Doctor and the Gentlewoman. The blood she believes is on her hands is from all those whose lives that were taken so that she and Macbeth could gain the throne and keep the throne.
She mentions Duncan, "'Yet who would have thought the old man to have had so much blood in him?'" (39-40). Then she goes on to mention the Thane of Fife's wife. It is impossible for Lady Macbeth to rid herself of her guilt as she begins the steady decline that ultimately results in her suicide.