The sisters' argument

I'm not super sure exactly what I'm supposed to do, so I'm just going to comment on the sisters' argument in the palace.
I think that Antigone was in the right by denying Ismene any share in the punishment. Because the "crime" that Antigone had commited was wrong only in Creon's eyes, the punishment was not a true punishment but an acknowledgement that the "perpetrator" had done right. For Antigone to be the only one sentenced to death wass to say that she was the only person to stand up for what was right, which she was. Antigone allowing Ismene to die by her side would have been a mockery of her action. Ismene wanted to die for selfish reasons that she made known by saying: "What do I care for a life, cut off from you?" She did not want to die for the Gods' wills, she wanted to die for herself. Antigone knew that she was dying for what was right and did not have any regret nor longing for a chance at life. "And if I am to die before my time I consider that a gain. Who on earth, alive in the midst of so much grief as I, could fail to find his death a rich reward?".