"I banished you to the moon Luna," Celestia said, her voice growing heavy with suppressed emotion. "After that, I lost more than just my beloved sister. I don't need to tell you of the pony I was after that, but as I came to terms with it, I found my will to fight had gone. I strived to create a thousand years of peace, not because I felt I had to, but because I couldn't face fighting a war without you. I just couldn't do it any more. Of course I had always preferred diplomacy, but I made some horrible agreements over the years if it meant not having to fight. I'm just thankful it all worked out in the end, because my hesitation to fight could have led to Equestria's downfall plenty of times."