Are you okay with Baihe :
Clear and Muddy Loss of Love(Qing Jun Mo Xiao)"请君莫笑"
https://www.mangago.zone/read-manga/getting_to_know_grace/
https://www.mangago.zone/read-manga/a_story_concerning_sweets/
https://www.mangago.zone/read-manga/the_sound_of_a_butterfly/
https://www.mangago.zone/read-manga/run_away_with_me_girl/
https://www.mangago.zone/read-manga/vampire_chan_junior_chan/
https://www.mangago.zone/read-manga/brides_of_iberis/
https://www.mangago.zone/read-manga/this_love_that_won_t_reach/ (age gap, MC is in love with her sister-in-law; rushed ending)
I second clear and muddy loss of love, shits peak
I need a doomed GL but with a happy ending. I also like it if it was a manhwa