In Macbeth, how has Shakespeare portrayed the character of "Lady Macbeth" after the murder of King Duncan ?

After Macbeth has performed the murder of Duncan, Shakespeare shows Lady Macbeth as the calmer, more rational of the two.  When Macbeth superstitiously panics because he could not utter the word Amen, she says, "These deeds must not be thought / After these ways. So, it will make us mad" (2.2.33-34).  In other words, she tells him not to dwell on what they have done or it will drive them insane.  Further, she realizes...

After Macbeth has performed the murder of Duncan, Shakespeare shows Lady Macbeth as the calmer, more rational of the two.  When Macbeth superstitiously panics because he could not utter the word Amen, she says, "These deeds must not be thought / After these ways. So, it will make us mad" (2.2.33-34).  In other words, she tells him not to dwell on what they have done or it will drive them insane.  Further, she realizes that Macbeth has brought the murder weapons out of the room with him, and she chastises him for being so thoughtless.  However, he is too emotional and refuses to return to the room with Duncan's body.  Disappointed in his cowardice, she says, "Infirm of purpose! / Give me the daggers. The sleeping and the dead / Are but as pictures" (2.2.52-54).  She returns the daggers to the room, smearing the chamberlains with blood, and when she returns, she calmly washes her hands, saying, "A little water clears us of this deed. / How easy is it, then!" (2.2.67-68).  Lady Macbeth seems very emotional and quite rational, even detached.  She is calm and clear-headed while Macbeth is frantic and prone to mistakes.  She has strength of purpose while he has none.