Lady Macbeth is definitely very interested in having her husband be king. Once he begins his homicidal spree, she has strong feelings of guilt.
Lady Macbeth becomes very excited when she hears that Macbeth has been prophesized to be king. She is ambitious, and wants him to have the biggest office.
Make thick my blood,
Stop up the access and passage to remorse,(45)
That no compunctious visitings of nature
Shake my fell purpose nor keep peace between
The effect and it! (Act 1, Scene 5, p. 20)
Lady Macbeth is interested in Macbeth coming into power at all costs. When he falters, she pushes him. She calls him a coward and tells him she has a plan, he just needs to follow it.
But screw your courage to the sticking-place,
And we'll not fail. (Act 1, Scene 5, p. 24)
Once Macbeth kills Duncan, she is still calling the shots. She scolds him for not putting the daggers by the victims. She insists that he play it up, and sound sincere. They both do an excellent job acting surprised.
When Macbeth does not stop at killing Duncan, Lady Macbeth is annoyed. She tries to stop the ball she started rolling, but Macbeth is no longer under her influence. She becomes more and more guilt-ridden, until she has a mental break.
What need we fear who knows it,
when none can call our power to account? Yet who would
have thought the old man to have had so much blood in(35)
him? (Act 5, Scene 1)
She eventually succumbs to grief and kills herself.