“We will proceed no further in this business.He hath honored me of late, and I have bought Golden opinions from all sorts of people,Which would be worn now in their newest gloss,Not cast aside so soon.”(Shakespeare,7)
This quote tells us that in the beginning  Macbeth is beginning to rethink the plan of killing him and he is starting to feel guilty already. Macbeth I sane and is thinking clearly as of right now because he thinks to sit s and ideas.
 Macbeth hasn't even done the act yet and he is starting to hallucinate seeing a floating dagger in front of him. When he starts to hallucinate he is then starting to lose his mind.
I have thee not, and yet I see thee still.Art thou not, fatal vision, sensible To feeling as to sight? Or art thou but A dagger of the mind, a false creation,Proceeding from the heat-oppressèd brain?( Shakespeare,1)
When Macbeth then starts to make a scene at dinner with everyone there, people start to begin to think he is crazy. He starts to hallucinate again and begins seeing Banquo at the dinner table in his seat.
(to GHOST) Thou canst not say I did it. Never shake Thy gory locks at me.(Shakespear,4)
Your castle is surprised, your wife and babies are Savagely slaughtered. To relate the manner, Were, on the quarry of these murdered deer To add the death of you.(Shakespear,3)
Macbeth has gone insane and has even gone far enough to kill Macduff's whole family and even his young children. He is to the point where all he cares about is his power.
When Macbeth is at war he hears screams and people dying and doesn't think much of it. He tells them that he forgot what the feeling of fear feels like and he is now gone insane when he says this.
I have almost forgotten the taste of fears.The time has been my senses would have cooled To hear a night-shriek, and my fell hair Would at a dismal treatise rouse and stir As life were in ’t. I have supped full with horrors.Direness, familiar to my slaughterous thoughts Cannot once start me.(Shakespear,5)
Macbeth has now gone insane and he will do anything for power and control of the kingdom. When he gets news that his  wife passes away he acts as if he never cared for her and goes on wth his life.
She should have died hereafter.There would have been a time for such a word(Shakespeare,5)