She would have died later anyway. That news was bound to come someday. Tomorrow, and tomorrow, and tomorrow. The days creep slowly along until the end of time. And every day that’s already happened has taken fools that much closer to their deaths. Out, out, brief candle. Life is nothing more than an illusion. It’s like a poor actor who struts and worries for his hour on the stage and then is never heard from again. Life is a story told by an idiot, full of noise and emotional disturbance but devoid of meaning.

This means that he is sorry about all the evil things that he have done at the moment  and because of that he said the life is too short and complicated story made by yourself and that only you can do once and it finishes, you can’t go back in the time sometimes great and another times bad but that is the life said Macbeth.