I'm looking for romance manga that "pains your heart''.

Unrequited love, Getting dumped, being cheated on, being "the other guy/girl", forbidden love, mutual love but not being able to be together, etc

Some examples:
emma
Girl friends
Strobe edge

Feed your head.

Nageku Shinigami
I Love You (HANATSU Yaya)
DOLL: IC in a Doll
A Million-Pound Love
Flowers of Evil <- i think you aready read this one

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Flowers of Evil
Truly tragic.

yeah, I've read flowers of evil

Feed your head.

oh yes, zettai kareshi (the end) and full moon wo sagashite (during the story) may also count. and for one "in-your-face" tragedy, there is kitchen princess

i think they are not on your list. FMwS is a must-read for painfull romance

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currently reading: Nyotai-ka
please support me

only thing I can think of is
Deep Love - Ayu no Monogatari
and Banana Fish though I don't think you'll like banana fish it has slight bl content. They are only friends in here and practically they need each other to live. They are total opposites (one of 'em is a gang leader and the other is an tourist) and that later leads to a tragic outcome. This isn't those fluffy fluffy watashi yuu or arina tanemura tragic kind of 'love'.
Phalene- one-sided(?) love that turned tragic
and...hmm
maybe Made in Heaven?
made in heaven might fit what your looking for. It's a tragic type of love when the guy knows he has a little time left to live and he thinks the woman he loves doesn't really truly love him as he does, if I remember correctly

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I hear you say "Why?" Always "Why?" You see things; and you say "Why?" But I dream things that never were; and I say "Why not?"

Donno if you have read them or not but here's some:

Cappuccino really good made me cry
Soko wa Nemuri no Mori Not the best one, but still pained my heart
Honey Bunny! the beginning was sad but didn't really like the ending
Heroine Shikkaku this one was really refreshing
Koishi Tagari no Blue another good one

And I think there is more but I would have to think about it... 🤢

kimi no iru machi

renai shijou shugi (i banged my arrow keys , and broke em out f rage)

maisson ikkoku

bitter virgin

ginen shounen

best shonen manga couples :

shinichi X ran
natsu X erza
ippo X kumi
naruto X gaara

Quote from ajcoolim107

maisson ikkoku

ginen shounen

If these two count then I think Yume de Aetara is another that needs to be added because the elements that "pain the heart" in those two are also evident in Yume de Aetara. Arguably even more so.

I'm surprised not to see Ai-Ren mentioned. It doesn't contain any of the elements in OP's post, what it does contain is

two people who both know they are going to die in less than a year live fall madly in love with each other and through each other experience true happiness. In the end Ikuru didn't even want to be rescued after the facility was attacked because he was content with the life he lived because he got to meet and fall in love with Ai.

Fukai Nemuri no Hana
Hyakuman Tsubu no Namida
Sorayume no Uta
From Kazumi Yuana are quite depressing and dealing with deep bonds between people, however its been long since i've read them and i can't remember if all of them are dealing with romance as the main "pains your heart" element ^^'

Honey and Clover - though I highly recommend the anime.

One-shots --
Hotarubi no Mori E (the title story) and Kon no Ki Konoha have a similar premise, but one ends with a much more tragic tone...

Some of the stories in Natsume Yuujinchou are like that... (chapter 2/episode 2 from the anime is an example... I know I cried hardcore for episode 8 in the anime as well).

Hanatsukihime may work, though the story is quite short...

Oh yeah The oneshot The Flower that Blooms in You I Won't Forget This Love

Savage Garden
Basara
Aegis
Doremifasollariso
Watashitachi no Shiawase na Jikan
Hoshi no Koe

And I second and third Banana Fish. If you're into shoujo, Hana Yori Dango is good though long.

May the curse of Mary Malone and her nine blind illegitimate children chase you so far over the hills of Damnation that the Lord himself can't find you with a telescope. - Irish Curse

I'm not your type. I'm not inflatable.

Cry me a river, build me a bridge and get over it.

Everyone is entitled to be stupid but you're abusing the privilege.

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Kare wa Tomodachi

saranghae SHINee <3

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