Cold and Lonely, Dark and Dim

Soon Luna found that, though she was freezing inside, the sun would burn her from the force of its glare, so she hid in the shadows of craters. She dared not go over to the dark side of the moon, and risk running into Nightmare Moon. Sometimes Luna could see her on the horizon, glaring malevolently at her, then fading back into shadow.

And so the days passed. Slowly, inexorably, the wheels of time turned. Luna tried to amuse herself sometimes by scratching games into the moondust with her hooves. More often, she laid her head on her hooves and sighed. She missed her sister, and the ponies of Equestria.

Loneliness crept over her, slowly but surely. She'd never before been this alone. Even when she thought nobody had liked her, there had always been somepony around, trying to comfort her or at the very least, serve her. Her sister had often been busy with her duties, but she had been there occasionally too, trying to coax her sister to come out of her rooms and make friends.

Now she was completely alone, though. She pretended to talk to her sister, the palace servants, anyone she could think of. Silence was the only reply.

Pain grew in her heart, threatening to shatter it all over again. All she could do was think, think about what she had done, how she had hurt her sister. What did Celestia think? Did she ever think of her little sister on the moon?

Sometimes when she was particularly lonely, she hoped she was in her sister's thoughts at least once in a while. She could not the stand the thought of having been forgotten, of being completely and totally alone in the universe.

On better days, though, she realized she didn't want to be remembered. Poor Celestia would probably blame herself for their situation. She would miss Luna terribly. Luna didn't want Celestia to be lonely too. It was better if she just faded from memory.

And why shouldn't Celestia blame herself? the echo of Nightmare Moon's voice reverberated in Luna's mind. She should have done more. She should have been there for you. She should have found a way to lock only me away, not you.

Nightmare Moon's insidious whispers found their way into her dreams, more often than not turning them into dark and twisting nightmares. That was, after all, Nightmare's specialty.

Flickering flames surrounded a massive, broken ruin. Luna walked through it, the flames shining in her tears, though she knew not why she cried. Around her, ponies bowed as she walked past, their eyes blank.

In the center of the ruin lay Celestia, her eyes closed, panting shallowly.

"Tia!" Luna cried, running to her.

At her sister's shout, Celestia opened her eyes.

"Oh, Luna, I'm so sorry," Celestia said. "You are the most powerful and beautiful pony there is. The night is more important than the day."

She smiled weakly. "Now you can have your night. I won't interfere. Everyone will love you, sis."

She closed her eyes and became still.

"No," Luna gasped. "No! Wake up, sis, wake up!"

"Help!" she cried. "Someone, please."

Isn't this what you wanted? Nightmare Moon's voice asked. She was never there for you anyway. It's not any different.

"No," Luna answered in despair.

Fine, Nightmare snapped. The dream changed.

"Everyone will love you, sis," Celestia said. She clambered to her feet, and bowed to Luna. "I am your faithful servant."

Luna woke up, crying and feeling deeply disturbed. She didn't want Celestia to serve her, did she? If only she could talk to her sister. She was so confused!

She began to feel so cold, so tight, so bare with loneliness, that she'd find herself wandering towards the dark side of the moon.

"Welcome," Nightmare said smoothly. "Nice to see you again. I do so enjoy our little conversations."

Luna shuddered, but stayed. She was desperate for company.

"So, are you going to 'un-banish' me?" Nightmare asked, making air quotes with her front hooves. Luna sighed. Nightmare invariably tried to find a way to convince Luna to free her. She wheedled, and pleaded, and tried to trick her, and made promises Luna knew she would never keep.

"No, Nightmare," Luna said wearily.

"Maybe I just won't talk to you today, then," Nightmare said, turning abruptly around and swishing her tail so it just - almost - touched the end of Luna's nose.

"No, wait," Luna said unhappily.

Nightmare turned back with a twisted glint in her eye.

"So we'll talk about releasing me?" she asked.

"No!" Luna burst out in frustration.

"Fine," Nightmare said, lowering her head and looking up at her with eyes that were squinted in an evil grin, though she wasn't smiling. "Goodbye."

Luna felt as if she'd been punched in the chest as Nightmare walked away. She couldn't breathe. Finally, as Nightmare disappeared, she fell to the ground and sobbed.