In Sophocles's Antigone, Eurydice is a minor character who makes only a brief appearance in the play. She is the wife of Creon, the acting king of Thebes, and the mother of Haemon.
In short, Eurydice kills herself because she is heartbroken over the death of her son. Let us take a closer look at some of the events that precede and lead to Eurydice's death.
Creon decrees that Polynices is a traitor to Thebes and that his body will remain unburied on the battlefield, where it will be exposed to the elements and animals. Creon also states that anyone who tries to bury Polynices will be put to death.
Antigone, one of Polynices's sisters, violates this edict and buries her brother. When Creon finds out, he has Antigone arrested and sentences her to death.
Haemon, Creon's son, is in love with and betrothed to Antigone. He begs his father to reconsider Antigone's fate, but his pleas are ineffective, as his father is convinced of his own righteousness. Haemon is outraged and heartbroken. He accuses his father of being stubborn and hints that Antigone's death will result in a second death (his own).
Creon decides that Antigone will not be killed publicly. Instead, she will be entombed and left to starve to death. After consulting with Tiresias, Creon decides to free Antigone, but this decision is made too late.
From a messenger speaking to the chorus and Eurydice, we learn of events that have occurred offstage. Eurydice hears a commotion and asks the messenger to tell her what happened. Creon and his men finish burying Polynices and are heading to Antigone's tomb to free her when they hear Haemon crying. Creon arrives at the tomb to find Antigone hanging from a noose. She has killed herself, and Haemon is distraught and blames his father for his beloved's death. Haemon tries to stab his father and misses. He then stabs himself instead and dies.
Eurydice is heartbroken by the news of her son's death. She retreats back to the palace. As Creon is mourning the loss of his son, the messenger returns and tells Creon that Eurydice has killed herself. She cursed her husband for his foolish pride and stubbornness just before stabbing herself.