Provided that your definition of "love" is a little broad and not aimed specifically at romantic love, then there are several cases when the characters show loving feelings towards each other. First, when Banquo and Fleance are attacked by Macbeth's hired murderers, Banquo fights with all his might against the men which allows Fleance to escape. One could argue that Banquo sacrificed his own life to save the life of his son--obviously such an action would be based on love.
Next, King Duncan says that Macbeth has won his love by being a dutiful soldier in the war against Norway. Duncan is a good king and his servants love him in return. This is one of the reasons why Macbeth is so conflicted over killing him.
Finally, one could also argue that there is a type of love based on loyalty between Seyton and Macbeth. All of the other Thanes in the kingdom have fled to join Malcolm and the English army, yet Seyton remains by Macbeth's side, possibly out of love for his king.
So, in these examples, loyalty is a type of love that motivates the actions of the characters.