In Shakespeare's Macbeth, the man we see Act Five, scene five, is a very different Macbeth than the audience has seen earlier in the play. When the story opens, one of the things we find early on is that Macbeth loves his wife. In Act One, scene five, Macbeth addresses his wife affectionately in a letter he sends her:
This have I thought good to deliver thee,
my dearest partner of greatness, that thou mightst not lose
the dues of rejoicing, by being ignorant of what greatness is
promised thee. (9-12)
However, by the time Act Five, scene five, arrives, Macbeth learns his wife is dead and he is rather cynical about it. Even as recently as Act Five, scene three, Macbeth has asked a doctor to look into Lady Macbeth's inability to sleep. The doctor notes that she has a troubled mind, and Macbeth cares enough for his wife to ask the doctor to make her well:
Cure her of that.
Canst thou not minister to a mind diseased,
Pluck from the memory a rooted sorrow,
Raze out the written troubles of the brain,
And with some sweet oblivious antidote
Cleanse the stuff'd bosom of that perilous stuff
Which weighs upon the heart? (46-52)
However, by Act Five, scene five, Macbeth accepts news of his wife's death almost casually—noting that it was inevitable...it would have happened sooner or later:
She should have died hereafter;
There would have been a time for such a word. (19-20)
I don't think Macbeth has lost his love for his wife, but things are changing so rapidly that I believe between scenes three and five, Macbeth is starting to feel as if his plans are not going to turn out as he had hoped: losing Lady Macbeth (he could be thinking) may only be the first disaster.
In Act Five, scene three, we hear how Macbeth defies anyone to believe that he can be defeated, as he relies heavily on the witches' predictions. Regardless of the reports arriving, he encourages the traitors who are joining Malcolm to go, for Macbeth is going to win:
Bring me no more reports; let them fly all!
Till Birnam Wood remove to Dunsinane
I cannot taint with fear. What's the boy Malcolm?
Was he not born of woman? The spirits that know
All mortal consequences have pronounced me thus:
“Fear not, Macbeth; no man that's born of woman
Shall e'er have power upon thee.” Then fly, false thanes,
And mingle with the English epicures! (1-8)
However, by the time Act Five, scene five arrives, Macbeth is again, not the same man we knew earlier in the play. He is no longer a strong and confident warrior—he is worried. The messenger tells him that he saw the woods move:
Let me endure your wrath, if't be not so.
Within this three mile may you see it coming;
I say, a moving grove. (40-42)
Macbeth knows that this shouldn't be happening: if it's false, he'll kill the messenger. If the news is true, Macbeth knows he is in trouble:
If thou speak'st false,
Upon the next tree shalt thou hang alive,
Till famine cling thee; if thy speech be sooth,
I care not if thou dost for me as much.
I pull in resolution and begin
To doubt the equivocation of the fiend
That lies like truth... (43-49)
Macbeth knows the devil has tricked him. He knows he cannot depend on success based on the predictions. He has lost his unmoving confidence. He is not the same valiant soldier, or the tyrant. However, he will die fighting.
This scene shows how dramatically Macbeth's situation has changed. The direction of his is moving toward disaster.