Correct me If I am wrong. Are you mentioning this part of the fifth act? In that case I highlight the lines where Macbeth tells the audience that Macbeth realizes his mistake and regrets his ambition.
Will chair me ever or disseat me now.
I have liv'd long enough: my way of life
Is fall'n into the sear, the yellow leaf;
And that which should accompany old age,
As honour, love, obedience, troops of friends,
I must not look to have;
but, in their stead,
Curses, not loud but deep, mouth-honour, breath,
Which the poor heart would fain deny, and dare not.
