Not the emotions hurt the most, only boredom and strange mortal swings.

@Joshua  
Because of luck, deus ex machina and plot devices…

@Background Pony #B23F  
But, those plans worked, right?

@Remains  
No wonder she went slightly bonkers. Sending a scholar, a farmer, a baker, a fashionista, a veterinarian and a weather pony to deal with a dragon as an example… amongst other similarly insane things she did throughout the series.

@Background Pony #B23F  
>”And she’d outlive them all, again.”  
Oh dear.  
Have you ever considered how stagnating this sounds? now repeat it infinitely.

@Remains  
*If she got serious, nothing could contend with her. At least beforr powerhouses like Twilicorn and Flurry came along…  
*Worst would happen is that some sort of hidden movement would form. And she’d outlive them all, again.  
*Bus she already misled everyone, about being the singular ruler and Luna’s existence…
 
Her morals? The same morals that allowed her to use the Elements without knowing the result, as pointed by someone before me?  
Also who said the Celestia we see nowadays has the same morals as the Celestia from 1000 years ago?
 
Nightmare Moon’s behaviour depends on whether that is Luna or Luna posessed. The episode with the AU’s kinda  
hints at the later. And the least it would do is surprise NMM.

@Background Pony #B23F  
You are assuming all of the following:  
*That none of Celestia’s enemies aren’t a real threat, or that they aren’t concerning enough.  
*That outliving someone is the easiest way or best approach to what would become a higher problem in the future.  
*That you can mislead everyone ever existing.  
Even if in theory Celestia is an absolute monarch, her morality alone wouldn’t allow her to exert most drastical decisions fully.
 
In your scenario, however, you’re missing the fact that Nightmare Moon simply wouldn’t “soften up” or that she would expect manipulation tactics beforehand.

@Remains  
And she should care why? She’s a (probably) immortal absolute monarch, what she says is law.  
She easily outlived any dissenters… Slowly changing history to “atone” for her own percieved  
mistakes would be easy.
 
So let’s use this scenario:  
Celestia cast Luna as a sacrifice in the books, holding a Nightmare for 1000 years;  
Nightmare comes back during the Summer Sun Celebration, she’s greeted cheerfully;  
If Luna IS the Nightmare, then this would probably get rid of the darker feelings (she wanted to be appreciated);  
If Luna is posessed by a Nightmare, the welcome would make her lower her guard and a better instructed group of friends  
(instead of “Go make some friends) uses the Elements and everything is alright.  
In both cases, Luna is wellcomed back and Celestia feels somewhat alleviated of her own guild.  
Win/win scennario.

@Background Pony #B23F  
>Why did Celestia censor history instead of twisting the truth to cast it in a more positive light to have ponies to talk about Luna to?  
It’s quite simple. When you’re a politician or ruler, even if you don’t hate your adversary (notice I’m not speaking about “enemies” in this case) you simply can’t depict your adversarial figure “positively” without infuriating your most fanatical followers.  
From a strategic viewpoint, this would be a horrible mistake - one which your other rivals would exploit eagerly.  
Most religious and political fanatics aren’t precisely the friendliest type.  
You lose their trust, they begin switching sides.

@Background Pony #B23F  
I like to think that she kept them as her own “tantabus” so she never forgets her greatest mistake. Also the ponies might not react very well to Celestia thinking fondly of what they equate as Pony-Satan

@Harmozel  
Dunno, Luna was very surprised when the darkness started to swirl around her…
 
As for observatories, ponies might have begun to appreciate the night on their own.
 
And as mentioned before, the only stained windows featuring Luna is the one with NMM, why would Celestia agree to it? Why remember Luna at her worst instead of best?

@Background Pony #B23F  
The flashback is just a mess and poorly thrown together.  
They equated Luna with NMM.  
We haven’t been given anything on that, maybe from the stars themselves.  
For the history part I can’t say much except you can only influence the records before you start outright doctoring lies. They do seem to celebrate the night given the astronomy towers everywhere.  
I think that’s Twilight being Twilight right there.

@darknessRising24  
Far from it, I love alicorn Twi and want to see even more power in her hoobes. The fact she now has her own student is adorable…
 
@Ardashir  
I don’t know, for there to be any celebrations there would have been witnesses to the fight. And from the flashback it looks like except the two fighting princesses and a time viewing Twi, there’s no one alive.
 
How did news about the fight even get out?  
Why did no one notice Luna’s absence?  
Who made the prophecy?  
Why did Celestia censor history instead of twisting the truth to cast it in a more positive light to have ponies to talk about Luna to?  
Why didn’t Twilight connect the elder sister from the legend to be Celestia?

@Ardashir  
The way she never breaks the Princess mask during those times astounds me. That’s sheer willpower right there.

@Background Pony #B23F  
And yet it’s still going on and even has three specials coming in 2017, if it truly “ruined the series” MLP wouldn’t have continued. EQG was their way of trying something new and it worked, as proven by the numerous sequels.
 
So grow up and stop acting like the series is the cancer of the fandom, because at this point you’re basically acting like those pretentious guys who think alicorn Twilight is a Mary Sue.

I wonder if for maybe years, maybe centuries, after NMM’s defeat, the ponies held celebrations honoring how their beloved Princess Celestia saved them all from the evil monster Nightmare Moon, complete with re-enactments.
 
Then there’s the way NMM was depicted for Nightmare Night.
 
Poor Celly.

@darknessRising24  
EQG is a continued attempt at gaining more sales by Hasbro. It, and several incoming spin-offs are promotional material for new toys.  
While the same can be be said about the main series, what with new oftentimes weird designs, but at least it stays somewhat true to Faust’s original vision (though less and less with each new weird toy and writer)  
The series is MLP: My Little Pony, not my medium-sized mutated humanoid.
 
As for WHY it ruined it, the show has a timeless, ageless message that could be understood by everyone in any country. Meanwhile, EQG is narrowing it to a very specific audience and uses increasing amounts of americanisms.
 
This combined with other factors causes these undesirables to seep back into the main show.
 
Relevant to this thread: Principal Celestia and V.P Luna.

@Background Pony #3169
 
@Background Pony #B23F  
If you two seriously believe that EQG “ruined” the series then you’re not only shallow and narrow-minded but you’re basically showing that you never had any respect for the series to begin with.

@Background Pony #3169  

Not to get off topic, but I think you will find that there are a fair number of people who would disagree with you on that. In fact, even among people who don’t much care for EQG, I’m willing to bet many wouldn’t consider it G3 levels of bad. Honestly, whatever faults you think it has, it has not “ruined” the main series.

@Background Pony #3169  
I agree that EQG ruined the current generation but can’t agree that Luna is in stasis - her interactions with the CMC are pretty straightforward and show at least some level of character development…
 
 
@Remains  
From what is implied about the Elements, they are never lethal, though I can see what you mean by Celestia not knowing if Luna would survive the banishment, considering what she saw when Sombra got banished  
That said, Celestia is one of, if not the only pony in existence who KNOWS what we can only speculate - are alicorns immortal?  
Because, sure, Luna did not survive the banishment from a mental standpoint.
 
As for people understanding - we can’t. We are not as long lived as Celestia or Luna do we can’t even begin to try to “put ourselves in their shoes”  
This is even worse in the fandom, as there are psychopaths out there (artists, writers and others) who would prefer to torture the alicorns (anypony, really) some more for their own sick, twisted pleasure.

@Joshua  
It’s not about the weight of guilt and defeat alone.  
Celestia might haven’t know about what the elements would really do to her sister.  
The Elements of Harmony are not just sacred and overly powerful. They very well could be dangerous to a deadly point.  
Celestia knew they’d imprison Luna, yes. But surviving said imprisonment… that’s different.  
They way I see it, Celestia was even doubtful of Luna’s chances of survival.  
After all, she had already assumed her little sister’s place. The Mare in the Moon, rather than a symbol of hope, probably reminded Celestia of a memorial.  
There was a thin line, and over it was the prophecy of the “stars will aid in her escape”.  
Prophecies don’t always come to pass.  
And some things meant to be eternal suddenly fade away, too.
 
To make it simpler, I think Celestia had the kind of grief you get when things just can’t get any worse, if you get it.
 
@darknessRising24  
Except some people don’t feel sorry for her.  
And one can’t blame them. Regret over a seemingly endless grudge is not something I’d expect most people to understand. While the show tries to make people ponder about concepts such as feelings, empathy and ethics, realistically speaking not many will really get the morals unless they’ve been through a similar situation before.

She’s crying on a character that’s on canon limbo (because the writers have to try to please everybody which is pointless),plus one who star on a spin-off that knocked back MLP reputation to G3 level so WHO CARES !

Actually, it’s 365,250 days if you count leap years. Not that much more more depending how you look at it, but tell her that.

@Background Pony #B23F  
They dropped the ball on it mostly during that flashback, it was very underwhelming and the way it portrayed Celestia during that left a bad taste in my mouth. DPDOMS left Celestia out completely and made Luna into a woobie. It could’ve been about how both sisters suffered for their fallout and how they rebuild their bond to be even stronger. I’m just disappointed they didn’t.

@Harmozel  
What do you mean by dealt with?  
As far as I’m concerned nothing really got resolved… After all, Tantibus happened…