I stand here, where I have stood so often before. My eyes close, and I reach out. This is easy, I have done it so many times. A moment of effort, and the sun begins to move for me, easing towards the horizon. The sky darkens slowly, and for a moment, I hold it at the edge, a crimson sunset covering the land. I do not see it, but I know how it looks, and I know some will gaze in wonder before I let it slip below the horizon.
Then my eyes open, and I turn my head, momentarily surprised that you are not standing there, ready to do your part. You have always stood there, you have never slacked at your duty. I feel a stab at my heart as I remember that tonight, this is my duty. I hold a moment, the sky dark, and my heart heavy and reluctant. Then my horn lights again, and I look towards the sky. I don't know this part as well, but I coax the stars from their hiding places, and the sky slowly lights with pinpoints of light. It doesn't look as lovely as yours... it doesn't even compare, and my vision blurs as the tears, held back for hours now, finally begin to flow.
Luna.. how many years were you angry? How many decades did you feel neglected? Why don't I know these answers? How blind could I be not to see how you felt? To dismiss your concerns as nervousness or silliness? You are my heart, and my harmony. The Elements are useless now, do you know that? Can you know anything in your prison? The Elements no longer respond to me. They are broken now, and so is my heart.
I blink back the tears to inspect my work. It's almost painfully bad.. the stars are clumped in groups, and not elegantly placed. Maybe it's my imagination, but I don't know how to do better. Except that something is missing... the moon. I sigh deeply, nearly a sob, and lower my head. I can not, I will not. I do not want to put the moon up there, for I know what I will see. That horrid shadow.. that will remind me every night of what I did, what I had to do, what I would now do anything not to have done.
Was it really the only way? You would not listen to reason. But you would not have had to, had I listened sooner. If I had wrapped my wings around you and softened the pain, maybe you would not have needed to lash out. Had I shown you that I love you just like I always knew in my heart I did. Did you know? Did you forget? Do you even now curse me for abandoning you?
I had to.. I HAD to. I had to protect the land, and I could not face you head on. Even if I had the strength I did not have the heart. You would have destroyed me, and I want to believe it would have been okay, but you were too angry. You would have destroyed all that we built together. Do you remember Discord, and all that we had to go through to free this land? It is bigger than you or I. There is so much good here. We can't let them suffer.. not for me.. and forgive me, please... but not even for you.
But right now.. as I lift my tear-drenched cheeks to the sky again, I would give anything to have failed, and let you defeat me. I close my eyes tightly, to close out the world, and my horn lights one more time. I fumble a bit, but I find the moon. Gently, slowly, I bring it up again. This is my tribute to you.. I know you can't see it or feel it, and I know the ponies who might be watching don't understand it's significant, but I don't care. I am going to do this right, for you.
Once it's in position, I open my eyes, and I look. Your shadow is cast across the surface... no. Not your shadow. Not my sister. The darkness that took you is there... and, no. It is not even you. Ponies will ask, and I will tell them the legend of the Nightmare Moon. Not my sister. Not my Luna. They don't need to know. Those who know, they don't need to remember. I will hold that secret to myself. I will bear the burden alone and your name will not fall. This is my fault, and your memory will not be tarnished.
The stars twinkle, and it catches my eye... there is something there, something to the pattern that I do not control. I watch a moment, I reach out with my magic and feel the forces at play - forces we only begin to interact with. It is subtle, and it is difficult to know whether I am imagining it. My eyes lock on the moon as my magic seeks around it, testing the cosmos and the very fabric of this reality. It's not the same as our magic, and it takes me a long time to understand. But, at last I know. This is not forever. You will break this spell.
I smile, gently. This is a reprieve, then. I have about a thousand years to learn how to break your anger. A thousand years until we meet again. Somepony will have the answer. I will do this for you, I will find that pony. When you return, I will show you how much I love you, and you will never, ever, feel neglected again. My heart will be whole again, and I will share it with you until the end of our days. By then, you will be legend, and you will be loved. This is my purpose. This is my promise.
"Until then, my sister."