Author's Note
This story was sparked by a crazy dream I had. There is no real premise for this story... non-cannon, maybe alternate universe. I am not sure I even wrote the characters into proper play. Go ahead, feel as free as always to rate, comment and or subscribe. 
I hate you...
There is only ONE chapter.
Luna sat upon her comfy pillow at her desk with quill and parchment laid out in front of her, the most bored expression she could muster drawn on her face. Over the last few hours she had been pondering how to start the letter explaining to her sister her true feelings. It was a requirement her beloved sister imposed on her, saying...
"Look, Luna, I know you do not like speaking your feelings aloud and have difficulty when it is troubled thoughts. So, once a month at least I would like you to write me a letter stating all the feelings you wish to convey but feel you cannot. It matters not what they are just as long as you get them out. Please, do this for us sister."
Luna churned her sister's words over in her mind a thousand times this month. She was truly at a loss for what to say to her sister. After-all, she realized within the first month how wrong she had been to bring the everlasting night. As a ruler she failed and she felt she continued to fail. Her night court was pretty much one of two things; a laughing stock or a place of fear. She had done her best to understand the new Equestrian laws and verdicts, though she had trouble keeping up. These small snippets did not seem to evade her sister who was, for all intense and purposes, still the same glory hound; to her at least.
Luna entered her own dream realm to buy herself some time to write the letter before sunrise. Hmm, okay... so maybe I could tell her how I feel she is a glory hound. I bet none have dared to tell her that! Haha! Perhaps I could... Her thoughts were interrupted by one of her dream's memories popping forth and Luna gasped.
"Hello, sweet Luna." The being of darkness grinned with her woeful fangs ever visible.
"Nightmare! Ha-how? Twilight rid me of you, how are you here?" Luna's mouth held agape as she looked at the suddenly bemused figure before her.
"Oh-hahaa, dear Luna. I feel it may be time for us to have a heart-to-heart chat. Don't you think? I mean, there are SOoOo many misunderstandings between us." A sly looking grin plastered Nightmare's face as she looked to her host. Granted, to Nightmare this was her best attempt to look disarming.
Doing a few breathing exercises her sister had taught her in the past when she got too emotional Luna readied herself and spoke calmly yet with a tinge of anger. "And what would a sniveling trickster like yourself wish to speak of?"
A smile beamed from Nightmare's face. "Oh, how wonderful that feels!"
For a few moments Luna looked at Nightmare, realization of what she was commenting on lost to her. "Do not fool with us, say what you have to then begone!" Anger was now within her vocals.
"Oh, such wonderful emotions my dear. You speak such truth of yourself with me but choose to curve your tongue towards your sister." The smile never left.
Luna Lula Moon soon realized what Nightmare was imploring. "What of it, so what if I do not speak angerly at Celestia. What does that have to do with you?" Eyes narrowing as she glared at the beast before her.
Shaking her head she rolled her eyes at the naive mare before her. Oh, how easy it would be to just take over again... though, I don't think that would help at all this time. "My dear friend, I think you fail to see it. You are truthful to your enemy but lie to your allies? I wonder, who it truly is that you view as your enemy. Dangerous ole' me; or your beloved and glorious sister, Celestia!?"
"I LOVE MY SISTER AND OUR FRIENDS!" Bellowed Luna in her royal Canterlot voice, anger evident on every syllable.
"OH, doth thee now!? Then how come thou cannot speak of how thy feel about thy sister, how thou feel betrayed, how we were BETRAYED!"
"She did not betray us, thou tricked me and betrayed her!"
"I did nothing of the SORT! She was the one that turned her back on us, thou only seeked me to help voice it!" Nightmare's anger filled Luna's vision as the memories of all those that shunned her for her sister's eye. She was nothing but a mere shadow, a lesser to them. Tears filled her eyes as she recalled asking her sister to help or to even watch the moon rise. Even then that would of been enough, to have her sister appreciate her nights once in a while.
During her remembrance she felt a firm yet gentle hoof bring her head up to face the one being she loathed. Wait... do I loath her? She could easily take me, the magic is strong still... why, why--.
"Because I am not a Monster." Tears fell from Nightmare's eyes as she looked deep into Luna's soul.
"I'm so sorry, I'm so.." Luna's words choked in her throat as she balled, her wailing only heard by a villain she had made.
The sun peeked through the window Luna had left open, her moon hanging on the edge of the horizon. Slowly she lulled it to settle across other lands. Rising herself she peered down at the parchment to have her vision consumed by a rather large pineapple. To the pineapple a sticky-note was placed, reading; To Luna from N.M. Pass the note she noticed the parchment filled with large letters that sparked unimaginable amounts of laughter from her. Not evil my flank. Thought the moon goddess with a bit more giddiness then she thought possible.
It didn't take long to prepare herself to greet her sister at their breakfast rendezvous, a meeting chamber Celestia had converted for the two of them. Privacy was something that the palace often lacked, although the room helped provide it a bit more. Luna had larger plans for privacy, but that would have to wait. Today was the day she would tell her sister how she really felt. Well, the letter would which would be the same, right? Luna grimaced a little as she was having second doubts about her idea and choice of words. They were only half-true, half... true. Luna readied herself as her sister made her entrance.
"Morning, Celestia."
"Morning, Luna."
Taking a moment to allow her sister to get comfortable before calling their servers over for their desired breakfast. Luna placed the pineapple on the table with a face that spoke volumes of being serious.
The action and the loud thump did not go unnoticed by Celestia who only raised a single eyebrow with the ease of a thousand years of practice could garnish. With a clam inquisitive voice, Celestia spoke.
"What is that for, sister?"
"It is for you, beloved sister of mine." Luna's voice seemed to hold a small amount of animosity that the two siblings could only pick up on.
"Oh?" Was the simple reply from the Sun Goddess.
"Yes, as well as the letter that is attached to it." A devious smirk of triumph had since formed on Luna's face as she gestured for her food to be brought forth.
With ease, Celestia levitated the rather large fruit in front of her and plucked the letter off and opened it. Glancing between the letter and Luna, Celestia's gut twinged as a feeling of disgust brushed her face for only a moment.
The letter had only a few words on it, though the few words spoke volumes to the celestial Sun Goddess. Volumes that played on their past, present and future together.
To Celestia.
GO BUCK-YOUR-SELF YOU DISGUSTING HORSE!
Sincerely,
Luna & Nightmare
P.s. I hate you, here's a pineapple.
Glancing back to her sister Luna happened to see the letter be engulfed in flames of destruction. Perking her voice up with as well as contorting her face to look a bit hurt and concerned. "Something wrong my sister?"
"Oh, no, nothing Luna. By the way sister, what were you doing when the Changelings invaded?" As Celestia picked up a knife and began woefully slicing the pineapple apart. Her own annoyance to the fruit evident on her every feature.
"I was being entertained by them." Was all the Moon Goddess stated.
With only a smile as she dove into her breakfast with new vigor, the weight she held on her chest for over a thousand years lifted as she dove forth. Today would be a great start, she could feel it in her soul, today would be a new beginnings for Luna.
Luna's honest remark and admittance to allowing an enemy to entertain her sparked Celestia's inner question.
"What do you mean... entertained?"
~FIN~
