Maybe you shouldn't have left her behind then, Madoka-chan? For all intents and purposes, you are as if dead. It's good that somewhere, by some miracle, she could find herself moving on rather than forever wallowing in the despair of her failure.
This comic is sad and sweet. It's kind of simultaneously heart-warming and heart-breaking that in all of these Mesmerizer after-stories Teto does her best to rehabilitate Miku from her insanity, then end up taking care of her when it never seems to work. At least Miku seems happy.