Heat Death
The sun grew weary of seeing men squander itβs light. Day in and day out, there was more pollution dampening its gift to the world. It wasnβt always like this, people used to love the daytime, respect the sun for bestowing light upon the world. The only way they could see without the sun was fire, but the sun disliked fire, due to the smoke. Those were the days the sun longed for, the days when its biggest worries were the ashes and smoke of a few fires lighting up the night.
Now, even during the day the sun was lesser, replaced with artificial lights that were always on. Around the globe, humans destroyed the sky, during day and night, with their selfish need to always have more. What the sun gave them was not enough, so they cast the sun aside.
Even when the sun began to heat the Earth as a warning, to stop polluting, to stop wasting, to stop destroying, they refused. Humanity had to be stopped, so the fires began. But the humans in charge could care less of their subjects, and so the war between humanity and its elements raged on.
Slowly, the day and night sky was blocked from the view of humans in some spaces entriely. The sun and the moon had communicated about this, but to no avail. The moon was young, and had no experience with this kind of thing. The sun was young too however, and childish compared to other stars. It begged their advice, but the stars scorned the sun. A star with whole societies that could not control its own solar system. They would not help a lowly creature like that. Rare few other planets had populations, and those civilizations were well under control.
The sun had no options. It was scared and embarrassed. It was out of help, out of options, running out of time. Soon the Earth had trapped so much heat the sun could not save it. The sun was forced to watch as the gift of humanity withered and died.
The sun carried this shame with it for the next billion years. In the last moments of its existence, before it was released from its misery its last thoughts were of the society it had failed. And, of the society that had failed it.