In Macbeth, what are the best examples of characters who lose hope of redemption when they choose the path of violence and betrayal?
Macbeth and Lady Macbeth best characterize this idea. Both plan and participate in the violent, bloody murder of King Duncan, playing upon his love and trust to slay him as he sleeps peacefully within their castle. When the deed is done, both wear Duncan's blood on their hands. After claiming Duncan's crown as King of Scotland, Macbeth continues to choose violence as the means to maintain his power. He coldly orders the murders of Banquo and Fleance (Fleance escapes, but Banquo is slain.), and in absolute cold blood, he orders the slaughter of Macduff's wife and children, as well as all his servants.
Macbeth continues his bloody rampage giving no thought to any spiritual redemption. After killing Duncan and before ordering the subsequent murders, he recognized that he had sacrificed his immortal soul for power, having given his "eternal jewel" to "the common enemy of man." Macbeth writes off any spiritual redemption for himself because he knows he has given his very soul to the Devil in exchange for the throne. Even as he faces death and reviews his life, Macbeth seeks no forgiveness. He merely acknowledges to himself that his life has been "a tale told by an idiot . . . signifying nothing." The only sign of regret he expresses can be found in his confrontation with Macduff in Act V. Macbeth does not want to fight with Macduff on the battlefield:
Of all men else I have avoided thee.
But get thee back! My soul is too much charged
With blood of thine already.
In this, Macbeth acknowledges his great sins against Macduff, but seeks no forgiveness or redemption for them, neither from Macduff nor from God. Instead, he chooses to fight to his death.
Lady Macbeth clearly believed she was beyond redemption for her deeds. Once her guilt engulfed her, she was destroyed by the weight of it. Afraid of darkness and tortured by her role in the deaths of innocents, she walks in her sleep and tries without success to wash imaginary blood from her hands, a sign of her deep psychological disturbance: "What, will these hands ne'er be clean?" Believing that her hands will never be clean because she is beyond redemption, she commits suicide.