In Shakepeare's Macbeth, Macbeth and Lady Macbeth appear to be in love and have a genuinely strong relationship--at the beginning of the play, anyway. This doesn't mean they aren't corrupt and that they don't possess warped values, and it doesn't mean they don't use each other to further their goals. But they do seem to be genuinely affectionate toward one another. The enotes Study Guide on the themes of the play says the following:
Oddly, among all of Shakespeare's married couples, the Macbeths of Act I and Act II show the highest degree of bonding and cooperative spirit. The very first time that we see Lady Macbeth, she is reading a letter from Macbeth prefaced by the fond salutation, "Dearest Partner of Greatnesse." There is in the first two acts of the play a mutual admiration between the two, a dual respect based on their shared conviction that the manly Macbeth is fit to be king, while the commanding Lady Macbeth is his natural consort. When Lady Macbeth is first told that Macbeth has executed their plan and killed the king, she cries out "My husband."
Productions of the play generally bear this out. The Macbeths are usually portrayed as affectionate and their relationship filled with physical contact.
And their thought processes, in at least one instance, are uncannily similar. When Macbeth enters the stage after his wife has read his letter outlining the witches' predictions, etc., she greets him with "Great Glamis, worthy Cawdor" (Act 1.5.52) and he greets her with "My dearest love," (Act 1.5.56) and the news that Duncan will be staying at their castle tonight.
They are both thinking the same thing. Lady Macbeth asks:
And when goes hence?
And Macbeth immediately replies:
Tomorrow, as he purposes.
The "as he purposes" demonstrates Macbeth's understanding of Lady Macbeth's implication (that Duncan won't be leaving) and his agreement with her implication. When will Duncan be leaving? He plans to leave tomorrow.
Macbeth and Lady Macbeth appear to be a well-matched couple.