This panel is so important.
Callie had spent this entire time wishing she could be alive with roxy and her friends. She wished she could be powerful enough to overcome her brother.
Now she’s seen what she could have been, but she’s also realized that what she wants to be is wrong. She’s finally starting to love herself and her flaws, and understand that the calliope that she is is perfect.
So she’s doing what god tier calliope is telling her to do. She’s finally going to live.