Road to happinesz

http://www.mangago.zone/read-manga/twilight_1/

http://www.mangago.zone/read-manga/kimi_ni_ienai_koto_ga_aru/

http://www.mangago.zone/read-manga/hitori_to_hitori_no_3650nichi/

Dont know if these are what you're looking for. But might be similar.

It’s not yaoi, shounen ai but it’s really good sad and happy.
Back in time to you

Stigma
Incidentally living together
Kakkou no yume
Cut (kawai touku)
Jazz for two
My starry sky
A thousand cranes
Koko Wa Yasashii Niwa