I hate to be such a stickler here, but my passion for ensuring that people don't get an inaccurate account of the story of True Tears and Noe Isurugi, just won't allow me to let this go.
So I still have to disagree with you here.
Noe Isurugi was Shinichiro's girlfriend.
That is how he once thought of her.
My interpretation of the ending of True Tears is that being "just friends" is impossible for Shinichiro and Noe, since Noe "makes his heart waver" (those are his
exact words, stated to Noe herself in an emotionally tense moment, going by the subs for True Tears' final episode that I had). To me, that's
anything but a guy that sees another girl as "just friends". That's a guy that
can't handle being "just friends" with another girl because she does cause him to have romantic feelings for her. This is much of what makes Noe's story even more tragic: Her relationship with Shinichiro is
completely ended; even the possibility of being "just friends" with him is gone.
Now, as it pertains to Hanasaku Iroha, I don't think Ko will meet as grim a fate as what Noe did, as I do think that Ohana will likely be able to at least be friends with him regardless of how it all turns out.
totoum is right that Ko might actually be more like Aiko than like Noe, at least in this regard.