@Background Pony #D01A  
Comics aren’t canon. They’re an alternate universe.

@Mysral  

@Mysral
 
Not to mention a good avatar, it seems XD

That bottom panel could be an amusing exploitable.

Not really a plot hole since the answer is in comics, check FIENDship is magic #4.

“I know this is a terrible shock for you, Twilight. And a terrible loss. But unfortunately, lessons like these are also very important to learn… even if they are also, very, very hard.”
 
“I… I… understand, Princess Celestia… I… I just don’t… N-no, I guess… I guess I don’t understand! Why, why would Starlight leave us all now? I… I really thought… O-our lessons… I… I really thought we were f-friends…”
 
“I know, Twilight. I know. As painful as it is to say, perhaps Starlight in your lessons with her learned something that she… didn’t agree with. And so she had no choice but to go away. Or maybe this was her plan all along.
 
Regardless, Twilight, know that I will ALWAYS be there for you.
 
ALWAYS.”

Hello there reaction image.

@Background Pony #EE16  
Molestia now has an official name, I guess? XD

KILL HER, SHE’S ONTO YOU!!!!

Starlight…  
Celestia has a split personality named Molly when it comes to dreams.  
I believe everypony was quite “satisfied”

That last panel, though…

I never noticed that plot hole most because I watch it for the “plot”

@orbsah  
That evil Celestia was the one controlling the dreams for those 1000 years, the same way Luna got corrupted by the gigantic power of the moon and night so was Tia in a way while she was in charge of it.

What is this implying?

I honestly think nobody did, not like it is crucial to any pony to survive, it just makes their lives much easier having a dream watcher.