This indicates that Lady Macbeth wants to be in control of her husband's mentality and the situation. To make herself believe that she is a different person shows how much determination Lady Macbeth has for her husband.
The determination Lady Macbeth possesses grows stronger through her speech. This is an attempt to overcome her silent conscience, which is present throughout. On talking of murdering the king she says, .
"To catch the nearest way".
This euphemism shows how fearful Lady Macbeth is of what she is forcing herself to accomplish. This also proves her loyalty to Macbeth-she will stop at nothing to fight her uncertainties, the battle between her will and her conscience. She may not desire for Duncan to be killed, but will do whatever is needed to please her husband. She metaphorically predicts the king's death as her soliloquy strengthens, .
"The raven himself is hoarse .
That croaks the fatal entrance of Duncan .
Under my battlements".
The raven is the given metaphor, which was known as a big, black ill omen of death. Lady Macbeth therefore links this symbol with her envisagement of the king being deceased. She admits she will be responsible for Duncan's death in the phrase, "Under my battlements", which is implied by the personal pronoun "my". The words "hoarse" and "croaked" are onomatopoeically associated with witches, showing the persona she adopts is evil and enchanted. .
The weakness of her character can be acknowledged when she asks for help from the outside world, .
"Come, you spirits .
That tend on mortal thoughts! unsex me here, .
And fill me from the crown to the toe top-full .
Of direst cruelty; make thick my blood, .
Stop the access and passage to remorse,".
The beginning of this quotation shows that Lady Macbeth feels she needs external help, as she cannot perform this notorious act with her mind alone. She wants to take away all that makes her a woman, e.g. love and pity, so she will be strong and without feeling (remorse).
