Lives change lives. Lives beget lives. Lives are lost. You can promise on your life with a straight look on your face and lie. Love makes the potential for that lie infinitely larger and smaller. But when you promise on love and mean it, you transcend the promise.
Everyone gets sad. Sadness is part of the human condition. Happiness as a goal is actually a very recent concept for people. Survival trumped happiness for most of our existence. Losing something hurts. And that’s always been around. Of course, there is a very large spectrum of pain defined by the person and the loss. But losing that transcendence is not just sad. It’s a loss of self.
Watching a life erode: if it’s your life, whether you choose to recognize it or not is self-chosen, and sooner or later, you figure out what’s coming and fix it, or self-destruct. When love erodes, it’s not just up to you, and it reveals beauty and terror. It’s mostly sad.
Eyes opening are a blessing, and eyes closing are fear. And the final closing most likely means oblivion. This is a metaphor.