I dunno, no matter how you look at it, getting back at someone for keeping a secret like she was because she was told to by most her superiors in the way she did by breaking her heart like that and people helping was cruel as hell, if that had dragged on for longer than it did I think I would have gotten way to annoyed to read to the end. The fact that it was only one chapter made this still a good read and I don't mind re-reading this. Though I still dislike Aina for what she did at the end, I can at least like her progression through the rest of the story before she went off the deep end.
I think it maybe wasn't as mean as all that. The way I read it, Aina was confused about how she felt about everything too, and the turning point wasn't until midway through that period when she went to visit the doctor to talk about it. That's when she enlisted people's help in working on a surprise for her, knowing that they'd soon be together again. Aina isn't the most adaptable person in the world, and you can see that throughout the story, so I can see her taking at least a few days to process things before realizing what's important.