霓裳羽衣舞出殇
[ní shang yŭ yī wŭ chū shāng]
In Chinese mythology and folklore, there exists a famous fairy dance named 'The Rainbow Feather Dress Dance'. Here the person uses this term and adds 'dance into sadness'. It may express someone is elegantly dancing alone while also hinting at the sorrow she experiences, maybe due to being lonely or losing something.