Just Cared Too Much - Guardian Ending Theme Song

[thisfanfeels]

In reading the lyrics, I can't figure out if this was sung by ZYL about SW, or SW about ZYL. In many ways, I guess they are interchangeable though I'm thrown off by references to "one year has past" and "walking the streets", "letting the hustle bustle continue", which seem to imply
1) post-deaths: one of them has reincarnated (?), living in either Haixing or Dixing, and is pining for his lost love.
Or,
2) pre-deaths: this is SW during that long 10,000 year period waiting to meet Kunlun again as promised (ref cdrama).

Any thoughts? Sorry if someone has already asked this in earlier threads!

https://www.youtube.com/watch?v=VNdZO4EdRco

(Newbie obsession unabated, day 3. Damnit, wished I could read Chinese and understand the original context as written)