Find the Courage and Strength to Move on.

In chapters eight and nine, Gilgamesh is in greif for is late friend. Enkidu had become his companion, his right hand, his morals, he had become a part of Gilgamesh. He remembers these times sadly. He later desides to go see Utnapishtim, because he feared that since his companion died he would be next, he supposedly knows how to avoid death. To get there he must go through different levels of the mountain ,all dark, its the cycle where the sun is set. I think this represents that you have to go through different stages of life to reach your goal, your rerward. Sometimes you may think, "ok this is it this one is the last obstacle, the last pace and you get another". That's what I consider the dark to be. Maybe its a persitance thing. What I mean by this is that since you think you're going nowere you have to convince yourself that it'll get better.
"You`re looking for something you can`t find If you give it up, you`ll lose your mind There`s always something in your way " Good Day- The Click Five

This connects to Enkidu's death because Gilgamesh has to learn to deal with such a significant loss to keep on gooing foreward. I find it interesting that this metaphor of the dark is right after the mourn over Enkidu.