The magic of friendship was helping me and my friends keep harmony throughout Equestria for many moons. But when the last of my friends passed away, I was left alone.
Of course, I had allies who were always by my side, but they could not replace my friends. Soon I noticed that with each passing year, I became more and more indifferent to my subjects and so did they. After much deliberation, I left my throne.
Then I dedicated myself to creating this dimension. I don't know how much time I spent on research, but I did it. Here I can live through favorite moments of my life. See my friends and family again. I understand that all of this is not real, but the emotions that I re-experience here fill my heart with joy.
What? No, I will never return to Equestria. Even if I wanted to. My physical shell no longer exists. All leftovers of my magic are aimed at maintaining this dimension. And I feel like it will soon run out completely. Therefore, you should leave this place.
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Thank you for reading this little piece of headcanon! I apologize for any grammatical or semantic mistakes. I am not a native speaker and I've never wrote fanfiction-like things before :b