Final answer:
Lady Macbeth's observation that Macbeth's use of violence is causing his insomnia is true. Macbeth's expression of guilt as the 'murder of sleep' shows the deep psychological impact of his actions.
Step-by-step explanation:
The statement that Lady Macbeth makes to Macbeth regarding the use of violence affecting his ability to sleep is true. In Shakespeare's tragedy Macbeth, the titular character experiences intense guilt after committing regicide, which is metaphorically expressed as the murder of sleep.
Macbeth expresses his torment in Act 2, Scene 2 with the lines, 'Methought I heard a voice cry 'Sleep no more! Macbeth does murder sleep, the innocent sleep.' These lines directly link acts of violence to the inability to find peace and restful sleep, indicating profound psychological and emotional distress.
Lady Macbeth, on the other hand, takes a pragmatic approach to their crimes and tries to strengthen Macbeth’s resolve. Nevertheless, it is evident that both of them experience a disruption to their sleep and peace of mind due to the violent acts they commit.