The effect of Lady Macbeth’s ambition and compassion towards her devoted husband is immediately shown in the first scene of which she appears. When she receives a letter from Macbeth informing her on his meeting with the three witches, who they promise him that he will be king. This is, in Lady Macbeth’s eyes, his rightful position and by her first words, ‘Glamis art thou cawdor/ and shalt be what thou art promised’ makes us instantly recognise that she will stop at nothing to make sure that he gets what she feels Macbeth deserves.
So when Lady Macbeth’s disturbing soliloquy about her becoming un-womanly to make sure her plan to kill Duncan will not fail, is not all of a surprise. She calls upon the spirits of evil in her quest to become completely absent of feeling and emotion. ‘Come you spirits, which tend on mortal thoughts/ unsex me here and fill me from the crown to toe/ top-full of direst cruelty’. She wishes for all her innate womanly qualities to disappear and replace it with evil ‘Come to my woman’s breasts and take my milk for gall’. She calls upon the evil spirits to prevent her in failing her mission to make her husband king. ‘no computions visiting of nature/ shall shake my fell purpose’. She asks for ‘Come thick night, and pall thee to the dunnest smoke of hell’ to hide her malicious thoughts and plans from everyone.