Someone asked a similar question.
http://www.mangago.zone/home/mangatopic/1068498/
Morcheeba has lists:
Unrequited love - yaoi/shounen ai
http://www.mangago.zone/home/mangalist/26111/
Unrequited love - shoujo/josei
http://www.mangago.zone/home/mangalist/26295/
Hmm...shoujo where the feelings remain unrequited till the end, huh? That's tough. The only one coming to my mind is "Kare No Aijou No Hakari" by Touda Yoshimi.
http://www.mangago.zone/read-manga/kare_no_aijou_no_hakari/
For BL manga with unrequited love I have already answered a similar question, which was linked here by "gamerg". Please refer to the answers there if you feel like it.
Can anyone please recommend me some mangas (BL, josei, shoujo) about unrequited love? especially the ones where it's still unrequited in the end, but well anything is fine! thankss!