Luna's banishment was more than a lesson she needed to learn, it was a nightmare. All alone in a frozen wasteland she was forced to call home. The mind is weak. Anything from isolation to torture can easily make it snap. Luna now knows about this better than she wished she did. All she wan't is to go home, but she knows it won't happen. Celestia doesn't care for her, nopony did. No one is going to help her, and the only pony she has to trust is one made from the hatred deep inside that she has denied for so long.