You have already read 1434 mangas/manhwas so you have probably the most popular ones already. Don't know if you read straight mangas/manhwas. If you read them then I will recommend - https://www.mangago.me/read-manga/the_girl_from_class/
For BL -
https://www.mangago.me/read-manga/back_in_time_to_you/
https://www.mangago.me/read-manga/loss_time_ni_hanamuke_o/
(I'll Recommend them because I guess you must've already read the most popular ones like haruka tooki e, December rain, an uncomfortable truth, Reunion, I'll be waiting for in 1999 or 10 years where I loved you the most.
If you want to read a tragic story only for the plot (with no romance) then I'll recommend - https://www.mangago.me/read-manga/the_horizon/
i wanna cry so badly