I don't think in your Aunt's situation the advanced directive made much of a difference. She did not die of starvation or dehydration. Can u imagine how much worse pain she would have been in if she would have keot alive in her pain and not been fed or given water? It would have been much worse for her. Her death was natural and not man made. Dehydrating someone to death is not natural no matter if they make a will say they want it or not.
My aunt did not receive IV fluids nor did she receive any feeding once she became unable to take anything by mouth. The morphine drip was mixed with a small bag of saline.
I do not believe in dehydrating or starving a patient. However, I watched helplessly while my aunt suffered excruciating pain. I prayed that God would, in His infinite mercy, take her to heaven so that she would not have to suffer anymore. That is, unless He would provide a miracle cure.
What good would a feeding tube and IV fluids have done her? It would just have prolonged the extreme agony that she was in.