At this point in drama, Creon has discovered that Antigone has defied his degree to leave her brother, Polyneices, unburied, food for carrion. She has made this choice under threat of death because she refuses "be guilty of dishonouring laws which the gods have stablished in honour."
Haemon has stood up against his father, Creon, in Antigone's (his fiancee's) defense. Creon threatens to kill her and make him watch. Haemon responds, "No, not at my side--never think it--shall she perish; nor shalt thou ever set eyes more upon my face," and he storms out.
Creon has sentenced Antigone to "hide her, living, in rocky vault, with so much food set forth as piety prescribes." (It was the custom for people to be sentenced this way, locked away with only a token amount of food and water, so their executioners would be able to say that they had not committed murder.)
The Chorus, at this point, waxes eloquent about how love can be such a wonderful thing, but it has here brought about this catastrophe among kinsmen. Antigone is led out of the palace, on her way to her doom, and the Chorus--the townspeople--say they weep for her, as she is "led to the bridal chamber where all are laid to rest." That is, she will now only been the bride of death.
Antigone replies that Hades will preserve her, and the Chorus agrees that this is so, as she is "mistress of her own fate." Antigone, however, hopes to be like the daughter of Tantalus (Niobe), who had been punished by the gods; they had killed her nine children and she fasted nine days until the gods buried them, at which time she was turned to stone yet still weeps. The Chorus points out that she was a goddess, but it's admirable that Antigone wants to be like her. Antigone responds as though they are making fun of her, though, and challenges them to bear witness to her burial, knowing she has no place on earth or in Hades. The Chorus responds but admitting that she is paying for her father's sin.
Her father was Oedipus, who murdered his father and married his own mother; even though he did this unwittingly, it was still a sin against the gods. Antigone agrees that this is all happening because of what her father did, and turns her anguish also upon Polyneices: "Alas, my brother, ill-starred in thy marriage, in thy death thou hast undone my life!" In other words, "If you haven't died in disgrace (forcing me to break Creon's law and bury you), I wouldn't be dying this way."
The Chorus seems torn. They acknowledge that her choice to bury her brother was right in the eyes of the gods ("Reverent action claims a certain praise for reverence"), but that she went up against a man with power and she has they "wrought" her own "ruin."
At this point, Antigone accepts her fate: she will die without a friend and no one will weep for her.