I need some angsty stories! Genre doesn't really matter, but I'd prefer if the story is sh...

https://www.mangago.zone/read-manga/boy_to_boy/

This got me crying i have no idea if this is anything like what you're looking for but this came first in to my mind when i read your questions. It's a bit long too...

Rofans-
https://www.mangago.zone/read-manga/how_to_get_my_husband_on_my_side/
https://www.mangago.zone/read-manga/i_thought_it_was_a_common_isekai_story/
https://www.mangago.zone/read-manga/i_became_the_hero_s_mom/
https://www.mangago.zone/read-manga/the_time_of_the_terminally_ill_extra/
Bls-
https://www.mangago.zone/read-manga/haruka_tooki_ie/
https://www.mangago.zone/read-manga/replay_1/ I think, I don't really remember
https://www.mangago.zone/read-manga/cloud_1/
https://www.mangago.zone/read-manga/bokura_ga_koi_wo_ushinau_riyuu/ I think don't remember part 2
Bls oneshots-
https://www.mangago.zone/read-manga/my_childhood_friend_was_a_god/
https://www.mangago.zone/read-manga/bebe_san_no_koibito/

(I'm not sure what exactly you mean by "angsty", but here are some that might be what you're looking for. Some of these are on the longer side, but they're all worth reading. Warning: may contain dark themes/images)
https://www.mangago.zone/read-manga/from_the_red_fog/
https://www.mangago.zone/read-manga/mononobe_koshoten_kaikitan/
https://www.mangago.zone/read-manga/isekai_shikkaku/
https://www.mangago.zone/read-manga/efforts_never_betray/
https://www.mangago.zone/read-manga/juujika_no_rokunin/
https://www.mangago.zone/read-manga/uratarou/
https://www.mangago.zone/read-manga/my_school_life_pretending_to_be_a_worthless_person/
https://www.mangago.zone/read-manga/kiichi/
https://www.mangago.zone/read-manga/kiichi_vs/ (sequel to the previous one)
https://www.mangago.zone/read-manga/bastard_hwang_youngchan/
https://www.mangago.zone/read-manga/three_days_of_happiness/
https://www.mangago.zone/read-manga/the_devil_s_boy/
https://www.mangago.zone/read-manga/unhinged/
https://www.mangago.zone/read-manga/phantom_tales_of_the_night/
https://www.mangago.zone/read-manga/switch/

https://www.mangago.zone/read-manga/ao_no_flag/
https://www.mangago.zone/read-manga/cloud_1/

Thank you, I'll try to read this if I don't forget (╥_╥)

Thank you!!!!!!!!! (⌒▽⌒)☆

I've never seen these series before, but I'll definitely give some of these a go (─‿‿─)

Cool! I hope you find something you like!