I agree with what epiphany212 said about how she behaves towards Draco as well as her attitude towards both her sisters, but I think there is quite a bit of love between her and Lucius. At the start of Deathly Hallows, when Voldemort is looking for a new wand and wants Lucius's, Rowling writes: "Malfoy glanced sideways at his wife. She was staring straight ahead, quite as pale as he was, her long blonde hair hanging down her back, but beneath the table her slim fingers closed briefly on his wrist. At her touch, Malfoy put his hand into his robes, withdrew a wand, and passed it along to Voldemort, who held it up in front of his red eyes, examining it closely."
Lucius is looking to her for advice, and without a word she shows him what's important. Granted, Voldemort is living in the house at the time, and it is in her best interest to go along with him, but I think it shows a lot about Narcissa's relationship with her husband that he's looking to her at his time of need, and she's helping him instead of coldly brushing him off as she does to almost everyone else in the room.