This is the catch-all for those stories that do not fit within the HP universe.
In the episode "A Canterlot Wedding", Twilight Sparkle is treated rather shabbily for most of the episode. No apologies happened on-screen. This is a possible interpretation of how the rest of the episode, and even the following episodes, came to be.
Even with magic available, destruction on the level caused by the changeling invasion is not repaired in minutes, or even hours. Because of this, it was necessary to push the wedding of Shining Armor and Princess Mi Amore Cadenza back a week. Twilight Sparkle, of course, made lists for each person, which were all duplicated on a master check list that was sent to Princess Celestia at the end of each day, with the days completed tasks marked off, and those in progress marked as such. Twilight resolutely refused to begin new wedding planning until the city was bad in top shape.
It was the end of the fourth day of repairs when the list appeared on Celestia’s table, but the packet seemed thicker than the past few days. For that matter, it clearly had not been sent by Spike’s flame, either, which also struck Celestia as unusual. Both Luna and Cadence were with her, as they were finishing their own duties in the city’s repair, and were getting ready to begin preparations for Cadence’s wedding.
“Perhaps Twilight has some new ideas,” Cadence said when Celestia commented on the unusual thickness of the scroll. “Shall we find out?” Celestia nodded and opened the scroll, and quickly proved to both of the other princesses that it was, in fact, possible for her to go even whiter.
“Oh dear,” was all she managed to say for a moment or two. “This is bad. How did we let this get this way?”
“What dost thou -” Luna began, and then scowled. “What do you mean, sister?” she asked. Celestia’s answer was to turn the enclosed letter toward Cadence and her.
Dear Princess Celestia,
I apologize for once again being a silly little foal, but I just can’t do this. I can’t go through the process of rebuilding the city and then rebuilding my brother’s wedding as if there is nothing wrong. It hurts too much to stay, so I’m returning to Ponyville.
The only two there who didn’t react badly to what happened were both ponies who weren’t there - Cadence was imprisoned, and Luna was dealing with the fact that she has many duties during the night and was sleeping when everything with the Changeling Queen took place.
I need to have some time to myself to think about things, because there is something wrong that needs fixing, and I have to figure out precisely what it is first, before I can even contemplate fixing it.
I give you a Pinkie Promise that I am merely going back to Ponyville, and will not run away to parts unknown to “find myself” or whatever the phrase might be. If I find that such will be necessary, then I swear to you that I will tell you and the girls first. Pinkie Promise.
I will also stay in contact through our letters, although I’ll need Spike around for any that follow this one. This one was easy, since I was in the castle, but over the distance between Ponyville and Canterlot? I can’t power it myself.
Your faithful student,
“Well, I can’t say that I’m too surprised,” Cadence said simply. “I would like to go to Ponyville to talk to her, however. I would like her there at my wedding.”
Celestia reared back slightly, as if Cadence had attempted to physically assault her. “You are not surprised by this reaction?” she asked.
“Not really. From what I can hear around the castle - and more precisely, what I haven’t heard - I don’t think that anyone has apologized to her for what was said and done. You all seem to be acting as if ignoring it will make the problem disappear. It doesn’t quite work that way.”
Luna glanced at it again. "She might be sick as well. This letter does not bear the usual mark of her … oh, now I go in the other direction!" She gently stomped her foot. "I am trying to sound less archaic. Her thoughts seem jumbled in this missive. Perhaps she wrote it and ran? I have my the letters she has sent to Celestia, and they are far more … I believe coherent would be the phrase. She doth be -” She sighed. “She is confused.”
“You’re doing fine, aunt,” Cadence told her. “I’ll help you with it, if you want. But yes, that letter is a bit disjointed. She hurts, some for how ponies reacted, but I suspect more for how they did not react once the trouble was over.”
Celestia looked quite troubled. “My last real comment to her, other than that she had a wedding to prepare, was that she had much to think on, and it was said in some anger. Let her know that we will have a long conversation when she returns, should she choose to. And that I have much to apologize for.” She hung her head. “Despite appearances, Cadence, age does not necessarily bestow upon you wisdom.”
“She is forgiving,” Luna said. “Perhaps too much so, but a truly felt apology will likely do much to ease her mind.”
“It will be given,” Celestia said, “but to her face. I will not trust something so important to a simple missive, no matter how long I might write it.”
She opened her mouth to say more, but was startled by the sound of hooves thundering outside her hall, coming to a stop outside. The door popped open, showing the culprit to be Shining Armor. “Princess! My sister! She’s missing! Everything from her room is gone!”
“We know, Shining Armor,” Cadence told him. “She sent a letter to Princess Celestia. Luna and I are going to Ponyville to see if we can convince her to return to Canterlot.”
He slumped. “She left because of me, didn’t she? I said such cruel things when she accused the Changeling Queen. I realized that, and was going to apologize to her. See if she might find it in her heart to forgive her idiot big brother, even though I don’t deserve it.”
“She has a huge heart,” Celestia said. “Luna is correct in that she will likely forgive. Right now, however, she hurts. Cadence, you and Luna take my chariot and be with her. Please - give her the thanks that I should have. I shall speak to her other friends to see if they have spoken with her.”