I think the character is Ismene; she was one of the two daughters of the marriage between Oedipus and Jocasta the other one was Antigone and had two brothers Eteocles and Polynices.
In the myth of "Antigone" that settles after the events of "Oedipus rex" the former king of Thebes stepped down overwhlemed by the tragedy that was his life and let the throne to be share by his two sons. At first they both agreed to alternate the throne every year disrespecting his father because he saw that as a negligent act. But after the first year of Eteocles as king he refused to let his brother take the kingdom and Polynices attacked Thebes to claim the throne. During the battle both brothers kill each other in a sword fight letting the kingdom in the hands of their uncle Creon who´s first command as king was prohibited Polynice to be buried becauses of betrayal to the homeland.
On that moment the two sisters had antagonist feelings; Antigone fear the divine authority over the human because she wanted to buried her brother and fulfill her duty as sister defendinf the family´s honor. On the other side Ismene decided to obbey the laws of men and tried to convince her sister to do the same thing but Antigone did not listen to Ismene and buried Polynices outisde Thebes getting caught by the King who declared her death sentence. Ismene declared her gulty even when she did nothing as a regret of her fear to the human authority over divine.
I hope the answer is correct and help you. I made a little resume about the myth to put in context why I think Ismene was the correct option.