Lady Macbeth's thoughts make her appear as cold and ambitious. To prepare for what she feels must be done she calls on evil spirits to "stop up th' access and passage to remorse" in order to be resentless. Otherwise she would not be able to complete the acts.
Lady Macbeth knows her husband well. She thinks he may be too kind in order to murder King Duncan. This is why she forgets her conscience so she can presuade Macbeth into murdering Duncan. At first Macbeth agrees. But later Macbeth ponders his decision. But Lady Macbeth is sure that being king is what Macbeth really wants and that this is the best for both of them.To make sure he will go through with it Lady Macbeth manipulates him by questioning his manhood and his love for her. She is successful because regardless of his own conscience Macbeth carries out their plan of murder.
The strength of Lady Macbeth also shows her her sneaky and devious ways.These are shown through her meticulous attention to detail about the murder. When Macbeth returns to their chamber she goes back to the murder scene and cleverly smears the guards with Duncan's blood. However, her morals had prevailed just a while before as revealed through her comment that she would have killed Duncan herself had he not "resembled [her] father as he slept."
Maybe Lady Macbeth felt that suppressing her conscience for the deed was enough and that later the thought of the horrible act woul go away. This is the oppisite of what becomes of her. Macbeth and Lady Macbeth often cannot go to sleep, and if they do, they experience nightmares. But still, Lady Macbeth is able to maintain her sanity...