I think what you are talking about it's actually a thai novel there's also the serie and it starts with the main characters dying but there's a good ending.
'The red thread' was it? I remembered someone ask abt that too here b4, they said that it not here yet but they send some link of the raws https://www.facebook.com/100329022284486/posts/118623460455042/
Yes that one
That's them from the fb post but i don't understand shit cause it's in Spanish ╥﹏╥
There's a bl which starts sad as the main characters die but i was informed it has a good ending, it's called "until we meet again" but maybe it goes by another name here cause i can't find it