Emily is nuts???

I did not anticipate the ending. I forgot about Homer Barron. So at the end when they started to describe a body of a man I did not immediately think of Emily killing him. But when I read the ending it began to make sense. There were signs of Emily's madness after her father died and she kept telling everyone that he wasn't dead. She stated it as clearly as a fact. But people knew for a fact her father was dead so this time they forced Emily to bury her father. Also there signs of her disillusionment from the way she shut herself off from the rest of the world. She also bought arsenic and didn't bother to tell the sales person what it was for. It seemed a tad shady to me but the sales person was so intimidated he gave it to her anyway...weird woman Emily was!