How does Macbeth's ambition lead him to his tragic demise

"We will proceed no further in this business. He hath honoured me of late, and I have bought golden opinions from all sorts of people" This being appropriate evidence that Macbeth had no intent or will to kill king Duncan. Macbeth wished to remain a loyal subject to his king as he had treated Macbeth so kindly and graciously. Lady Macbeth however, became angered and unpleased with her husband's attitude; it was then in her attempt to satisfy her own ambition that led to her manipulation of Macbeth to take King Duncan's life. Lady Macbeth hastily manipulated Macbeth with tactful spite by questioning him and his manhood alike. She worked quickly with the sting of her tongue, belittling Macbeth, suggesting that he is weak and frightened; until he was pulled into her vicious taunts for fear that he may be perceived in such a way. This became adequate motivation and ambition to kill King Duncan. This is demonstrated when Lady Macbeth says "What beast was't then that made you break this enterprise to me? When you durst do it, then you were a man; And to be more that what you were, you would Be so much more the man" Despite Macbeth's unwillingness to perform the act, he still had visions of a dagger created within his mind, this suggesting subconsciously he had the ambition and will to kill King Duncan. Macbeth being so easily manipulated by his wife to take the life of his beloved king derived even stronger ambition. This ambition only began to grow for being king ultimately was not enough.
             Macbeth had hardly been satisfied with the means in which he went about to become king. It was the lingering guilt of King Duncan's bloodshed that had left Macbeth feeling uneasy and insecure of those surrounding him, he was willing to go to any extent to prevent those around him to finding out the truth. Macbeth's guilt is portrayed when he states, "Will all great Neptune's ocean wash this blood from my hand? No, this my hand will rather the multitudinous seas incarnadine, making the green one red" "To know my deed, "twere best not know myself.