What are the main differences between Macbeth and Lady Macbeth?

Both of the Macbeths are ambitious, but Lady Macbeth lacks the strength to deal with all the consequences of her ambition.  In Act 1, sc. 5, when Lady Macbeth reads her husbands incredulous letter about the witches and their prophecies, she immediately knows that she wants to kill Duncan.  She doubts, however, that her husband has the drive to do the deed.  She goads him into killing Duncan by telling him he's not a man in her eyes unless he does this act.  She knows her husband wants to please her she uses that against him.  Macbeth never does anything like that to Lady Macbeth, however.  In fact, he shields her by not telling her, even, of his intent to have Banquo killed, Act 3, sc. 2.  By the beginning of Act 5, Lady Macbeth has gone mad from guilt and in Act 5, sc. 5, she dies, presumably by suicide.  She did not have the strength that she doubted her husband possessed earlier.  Macbeth, on the other hand, has become determined to ride out the consequences to their natural conclusion.  In the last act, Macbeth is seen as a tyrant, but a valiant tyrant who has not given up the fight.  In the last scene of the play when Macbeth and Macduff meet up again, Macbeth says he does not want to fight Macduff because he's killed enough of his family already.  When Macduff tells Macbeth of his birth and Macbeth knows he was tricked by the witches, he still does not give up the fight.  He is stronger than his wife.