Death

I used to hate story books with sad endings. I would flip to the very end of the book to make sure I was reading a "feel good" book. Now, I like all kinds of books. Some books have happy endings, some sad, but most of the time the endings are both happy and sad. Those are the most difficult endings to accept, a mixture of emotions that is best (yet not quite) described as "yearning for completion". These endings are endings that never end. Not a mystery or a cliff hanger but just,

The end.