How and why does Macbeth and Lady Macbeth's relationship change during the play?

Initially,and Ladyare the ultimate power
couple. They are both committed to 's murderalbeit with varying degrees of commitmentand see
Macbeth's subsequent elevation to the throne of Scotland as fulfilling his destiny.

There is a sense that once Macbeth has achieved his wicked goals,will attain a position
of equal power and authority within the kingdom, since without her, Macbeth would not have been
able to rise so far and so fast. She was the main mover behind the plan to assassinate Duncan;
she was the one who constantly cajoled, bullied, and pleaded with Macbeth to go ahead with the
murder when he seemed to be getting cold feet. It's not unreasonable, then, for Lady Macbeth to
expect great power to come her way once her husband is safely ensconced on the throne.

But that's not what happens. Once Macbeth becomes king, his wife fades from the
picture, marginalized and ignored by the man she whom helped to grab the biggest prize. As
Macbeth descends deeper and deeper into outright tyranny, he finds that he no longer needs his
wifehe can rule just as well without her, he thinks. Thehere is that it was Lady Macbeth's sheer
bloody ruthlessness more than anything else that led to Macbeth's becoming king of Scotland. Yet
now, as he develops into a blood-thirsty despot, he makes increasingly cruel, barbaric decisions
on his owndecisions that (again, ironically) Lady Macbeth would almost certainly not have
advised him to make.