O.o Okai, here are some but just to make, tragedy doesn't always mean someone dies in the ones I've listed. Just some really good enotional drama and sad bits in there. Some of the manga do have death or seperation tho.
This series has three parts and this is the prequel i think:
http://www.mangago.zone/read-manga/hana_no_miyako_de/
All the manga by this author is so EmOtIOnaL, but these two I cried the most in:
http://www.mangago.zone/read-manga/scarlet/
http://www.mangago.zone/read-manga/beautiful_days/
These are longer ones, But they're SO GOOD:
http://www.mangago.zone/read-manga/ze/
http://www.mangago.zone/read-manga/love_mode/
This one hasn't updated on years but it's pretty good:
http://www.mangago.zone/read-manga/sora_o_daite_oyasumi/
THE FAVOURITE OF THIS ENTIRE YEAR (I CRIED SO HARD MY EYES HURT):
http://www.mangago.zone/read-manga/life_senjou_no_bokura/
A two part series:
http://www.mangago.zone/read-manga/kimi_to_parade/
http://www.mangago.zone/read-manga/paradise_view/
Pretty long but unfinished:
http://www.mangago.zone/read-manga/sex_pistols/
Not tragedy but it's by the same author and it's pretty good but not finished yet:
http://www.mangago.zone/read-manga/natural_doggy_s_diary/
this list could go on forever sry, but these are the ones off the top of my head.
Idk why everyone loves these stories. The only interesting one was the first ones. The rest just seemed like cheap attempts at tragedy. :/ maybe I've read so much tragic books my expectations have shot up ( ̄へ ̄)