Everyone knows of Twilight Sparkle, personal student to the princess of the sun, and element of magic. She has friends, family, and above all, hope.
However, Twilight Sparkle doesn't exist. In fact, Equestria doesn't exist either. All it is and will ever be is a figment of my imagination. Simply a way to live out the rest of my days with a slight measure of happiness. I am not her, but I would give my horn to be her for but a single day. To have everything, and yet not realise how lucky you are to have such things, to live.
What I am doing right now is not living, this is waiting for death.

Traducción Española: https://www.deviantart.com/spaniard-kiwi/art/Futilidad-990270691

Luna struggles with the edges of sanity and feelings of depression after her time of lunar isolation.

First contact. Not just with a new world, but with a world in a whole new universe. Initial negotiations go well, so Princess Celestia makes a visit to this 'Earth' to cement peaceful relations. Unfortunately, even when you are as experienced as the goddess of the sun, it's the little things that can trip you up.

Preread and edited by Noe Carrier. SPOILERS IN COMMENTS!
Russian translation: Все это скоро закончится, принцесса by Smikey

Twilight has just wrapped up synthesizing a chemical in her laboratory, but starts to have an interesting day when she accidentally doses herself with it.

When Twilight Sparkle slipped beneath the covers last night, everything had been fine. She had friends whom she loved, a teacher she adored, and a bright future ahead of her. But when she woke up, her blankets and quilts had been replaced by hospital gowns and padded restraints.

Everything is wrong and nothing makes sense; even her friends have changed. The doctors keep telling her that she is sick, that none of it was real and that it was all in her head. Yet she remembers a life far beyond the hospital walls. She couldn't have made it all up on her own. They must be lying… right?

Ask Asylum Twilight - Still updating regularly!
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Art:
Asylum Cover by conicer
Twilight and Twilight Smiles by dreamingnoctis
Mirror Twilight and Plague Doctor by Jaestring / BloodGoldWings
Twilight Smiles and Doctor AJ by conicer
Nurse Ratchet and Silas and What's in the mirror? by Archonix
Doctor AJ Sketch by Archonix | Colored and vectored version by ReFro82
Twilight's Asylum by Khan the Cake Lover
Smilight by HappySwitch
Twilight Waking Up by Dombrus
Fan Art by toxicdemon10
Asylum Twilight by Madness-With-Reason
Asylum Fluttershy and Asylum Ch 26 by Downburst-Backspace
Twilight and her Twin by v747
Birdgirl by sirValter

Readings and Videos:
Asylum Animated Trailer Video by formuladash
Reading by Gammarobot (SugarCubeRadio): All Chapters Here
Reading by Ender Brony: All Chapters Here
Reading by VisualPony: All Chapters Here
Reading by MelancholyIguana: All Chapters Here
Fan Trailer by Kaidan: Asylum FanFic Trailer Cuckoo's Nest

Sanctuary by Kaidan
Broadhoof Files: Dr. Humors by TypewriterError
Broadhoof Files: Corporal Phalanx Spear (Ret.) by Phalanx Spear
A Hearth's Warming Tragedy by Seven Fates

A special thanks to Breath of Plagues, Rex Ivan,
ChudoJogurt, Cynewulf, Death the Kid, Selbi, PrinceDolph, Blahman2816, Queue, and Gage!

Axan Zenith - Dr. Dreamer
Dratini4 - Way Finder
psychicscubadiver - Bright Mind
Velkaden - Dream Chaser
Reese - Silver Glow
Viola Heartstrings - Clover
Archonix - Spinney Whiteacre

Being a princess is stressful, but your peers and friends can certainly help.

That was what Twilight had in mind when she invited Luna over for tea one afternoon. A relaxing, friendly meeting between two fellow princesses where they can commiserate and share their experiences. An invitation to a stronger friendship than they had before, offered to a pony displaced in time.

What she got was an uncomfortable assertion about her relationship with her number one assistant, Spike. One that she is having difficulty refuting.

For Luna, nothing ever seems to go right. Except when it does, it's wrong.

Twilight isn't having a very good day. An experimental spell blew up in her face, an army of changelings is attacking Canterlot, and she just died. Yet somehow, it looks like it's going to keep going downhill from here.

Given the chance to correct what's gone wrong, Twilight swears she's going to fix all this even if it kills her. Which it will. Frequently.

Cover art by Pixel Prism
Spanish Translation
Series TV Tropes page

The nightmare of that evening haunts my every waking moment.

A flash of light.

Her powerful form with wings spread wide before me…

She was not just my mentor.

She was also my best friend and for that I will always be grateful for knowing her not as a Princess of Equestria, but as Celestia… The only one who really understood me...

But now? Now I can never tell her how much I truly loved her and how much she meant to me.

They took her away from me.

So I will take everything away from them.

There is a sequel! D=S-M2 and side story! D=S-M: Emerald Mirror

((Somehow Featured on: 12/03/2014 and again on the 06/07/14... mad.

Much love and all credit to the artist: Ventious who owns that picture and is all kinds of awesome. While I have yet to get permission (working on that one at some point), I will remove the picture if the artist demands it so.

And much thanks to these guys for helping me edit/proof and generally bounce ideas about this monstrosity: Grammar Nazi Tach, Discorded Discord,Curify, Lord Inquisitor
TheAccidentalBrony))

Ten years ago, Twilight made the ultimate sacrifice in order to defeat Tirek. Equestria has been in a state of civil war ever since.

Canterlot has at last fallen, and the six heroes of the rebellion now go to face the ultimate challenge: defeating the godlike Twilight Sparkle. What they expect to be a brutal, hard won quest for glory and Equestria's salvation turns into something entirely different... and now they face a choice.

This story is a reaction piece against the Tyrant Sparkle trope.

Special thanks to Absolution for pre-reading and Danger Beans for proofreading.

Cover art credit: BluestreakFUS

Now with a Chinese Translation courtesy of Hellagur.