This is a very good question. In Sophocles's Antigone, the heroine is betrothed to marry her cousin Haemon, the son of Creon, who is now King of Thebes. Whether she loves Haemon or not is another matter. It is clear that Haemon loves Antigone very much and cannot bear to continue living without her. However, Antigone does not show much love for Haemon, or, for that matter, anyone else who is still alive. All her attention is focused on her dead brother, Polynices.
Creon and Ismene both criticize Antigone for loving the dead more than the living. She is willing to risk her life to ensure that Polynices receives at least a symbolic burial. However, it is not clear that this self-sacrifice is based on love for her brother.
Paradoxically, Antigone's self-sacrifice may be based on a form of narcissism, since she regards her own sense of duty as being more important than anything or anyone, living or dead. Critics and readers have long debated whether Antigone is right in her conflict with Creon, and some, like Hegel, have come to the conclusion that the two characters represent competing virtues. Another perspective, however, is that they are both cruel to those around them, cherishing abstract principles rather than love for any human being.