What evidence is there that Lady Macbeth is not as strong as she would like to believe, in Act Two, scene two of Shakespeare's Macbeth?
What does she warn Macbeth about regarding the dangers of thinking too deeply on their deeds?
In Shakespeare's Macbeth, Macbeth returns from killing the King and he is hysterical. It's as if his mind cannot grasp what his hands have done. He tells his wife that the guards were saying their prayers in their sleep as he entered to kill Duncan, and that when they said "Amen," he could not, though he felt that he needed a blessing.
Lady Macbeth encourages her husband not to dwell on it, but he cannot separate himself from what he has done. Still, Macbeth obsesses on trying to find the reason that he could not say "Amen" as well.
Lady Macbeth finally says:
These deeds must not be thought
After these ways; so, it will make us mad. (II.ii.33-34)
She warns him that this kind of worrying will drive him (or them) crazy. This might be an indication subconsciously on Lady Macbeth's part that she is not as strong as she thinks. However, I think she is actually quite capable at that time, but her situation changes later. I would imagine that Shakespeare uses this bit of foreshadowing not only to hint at Lady Macbeth eventual mental collapse, but I find it interesting that he presents Macbeth as the weak one and his wife as the instigator at the beginning of the play, and then demonstrates how they have switched places by the end of the play.