After Twilight escape she look for a spell to save her friends. But didn't find anything. Feeling she have failed she decide to leave Equestria and everyone she know behind.

Twilight: I can't believe Discord bring back three villains, and make their job possible. Now thanks to him Equestria is doom, and I'm a fraud and no longer a princess.

Twilight heard a loud growl and turn around to see three Windigos above.

Twilight: The elements destroyed, the school of friendship shut down, the pillars defeated, and now my home destroyed. Looks like Tirek, Chrysalis, and Cozy Glow has won. Nothing that I do matters. Maybe I'm the one who is a failure. Everypony is blinded by fear they can't remember what friendship is.

(No longer mourn starts)
Twilight:
"I am useless."
"I can't save my friends."
"Maybe I'm not their only hope."

Look in the mirror
A princess is what you see
That’s what they all expect from me
But they don’t know!

Since I gained these wings
I was told one thing
This mare is nothing
Without her friends!

What did I possibly do?
What karma is this cruel?
They were just right there
How is this fair?

The map is burned
The pages torn
And this alicorn
Will no longer mourn
I’ll no longer mourn!

It was all up to me
(It was)
Restore, then be free
But I failed and condemned
I can’t face them
(How could you)

Both friends and family
Are broken ‘cause of me
I don’t deserve to wield
The Elements
(Elements)

I was their only hope
Now they have to cope
Oh what is wrong with me?
Please set me free!
(Are you kidding?)

Everything was perfect when you were all here
Maybe it’s better if I just went and disappeared
(Go, go, go, go)

The map is burned
The pages torn
And this alicorn Has a lesson, has learned

Meeting has adjourned
I have confirmed
That is alicorn
Will no longer mourn
(Forever Severed)(ah ah)
(We need you)(ah ah-ah ah)
(Forever Severed)
(Don’t leave us) (ah ah)
(Don’t walk away)
(ah ah-ah ah)

Will no longer mourn
I’ll no longer moh-ah-ourn!

(Song ends)

Twilight: Goodbye friends.