I think it also has to do with COM being one of the first games release so post that we get Roxas full development of feels, TAV adventure of sadness, Xion's self acting soap opera and even Axel joins the group too. So it does come down to some perspective in thinking well Namine didn't die to save her friend, or lose her friends in tragic ways, or went on a quest to find out who they really are etc. She more or less had her 1 friend she meet for about 15 minutes pick another girl over her.
Yes she was force to manipulate characters like Xion/Roxas and even Riku to an extent, but I think people/fans just gravitate towards feeling bad and sympathy towards the people being manipulated rather than the manipulator herself.
The part about Namine actually doing bad stuff which separates her from the group is something I never thought about but it seems it has merits. I can't really think of anything Roxas/Ven/Aqua choose to do with full intents of hurting somebody without it being born of naive or something.
I do find it a bit amusing that her one big connection left that is sort of important in the series is Sora thanking her, but that's become more of a Sora thing than a way to show the bond Sora has with Namine.
You have also to keep in mind that during CoM itself, the whole premise was different as Naminé was first introduced actively doing something despicable to the protagonist which obviously affected him negatively. Xion's negative impact on Sora was not only passive, but was also only
possible because of what Naminé did during CoM. In order for Xion to absorb Sora's memories through Roxas they had to be unhinged first so they could trickle into Roxas through his direct connection with Sora, thus the action of messing up Sora's memories was actually the catalyst for the eventual fates of both Roxas and Xion.
With Roxas and Xion, as well as TAV, we're initially introduced to people who only mean well and do not take actions that are actively harmful to other good characters, making their suffering and pain much more obvious and present from the start.
Axel doesn't even belong in that group, but, ironically even more into the same group as Naminé, as he too did some despicable things along the way and, unlike Naminé, does not seem to feel as much regret about it.
The reasons why Axel's "suffering" is more prominent than Naminé's and his despicable actions are often more easily forgiven as hers are a) because he's an ensemble dark horse fanservice character who's
extremely popular and b) most of his despicable actions were directed at antagonists or villains even worse than him, not beloved "good" characters like Sora, Xion or Roxas.
The sole exception to this is the Riku Replica, who was really badly abused and used by Axel for his own ends (which is also ironically the only despicable action Axel
does seem to feel regret about, as one Secret report of Days shows), but since the Riku Replica gets even more overlooked than Naminé herself, this issue also gets swept under the rug often.
I'd rather say that to the majority of the audience, characters who get to suffer and feel pain that have not done anything wrong tend to get more sympathy by default, while characters who suffer but did some bad things, regardless if done because they wanted to or because they had no choice, tend to receive at least partly some "you deserve some of it for the shit you pulled"-mindset.
The only "type" of character who seems to exempt from this attitude is the brainwashed/possessed one as they have really no way to somehow prevent the bad things they do.
Naminé also didn't have any conscious intent to hurt somebody, otherwise she wouldn't feel so guilty about it constantly.
It is however true though, as I stated already above, that the premise with her was totally different to what we were shown with Roxas, Ven, Aqua and even Terra.
It's somewhat idiotic, I agree, not to mention that the whole "thanking" thing actually drowns out the
actual promise Sora gave her at the end of CoM:
CoM said:
Sora: No, not goodbye! When I wake up, I'll find you. And then there will be no lies. We're gonna be friends for real. Promise me, Naminé.
Sora promised her that someday they will be real friends, and that promise has yet to be kept.
Naminé herself does hint that she can come back someday with that promise though:
CoM said:
Naminé: Don't worry. You might forget about me...but with our promise, I can come back.
Sora: A promise is a promise.
Naminé: Yes. One day the light---it will be ours, and it will bring us together. Til then---I'll be in your heart.
At the core, there is much more than a simple "Thank you" to the connection between Naminé and Sora.
While your first point is true, I think it boils down to Namine's pain not being as obvious as the other characters. So if you think it through the whole thing ,then sure her suffering becomes more "legit" but I can understand that can get lost in the shuffle when you have scenes where Xion dies in Roxas' arms.
I think because she's Kairi Nobody and Kairi hasn't done much in the series leads to Namine not being in the forefront of the plot as of late.
Part of this may also come from Naminé herself not
stating/showing her own pain as many of the other characters do, which may actually also stem from her conviction that she
doesn't deserve to openly show her own pain because she caused so much pain to others.
These quotes of her underline that pretty good:
Naminé said:
Sora: Don't be. Please don't cry...
Naminé: Oh... Of course. I know I really don't have the right to.
Sora: That's not what I meant!
Naminé said:
Naminé: I may be gone, but my promises to him are forever.
And anyway... I owe this much. For all the...all those people that I hurt.
This shows that Naminé is really putting much blame on herself, with especially the Coded-quote obviously including Roxas and Xion too because she speaks of
multiple people she hurt with her actions.
That in order to help Sora and fix the "hurt" she did to him she had to hurt other innocents in the process obviously did affect her severely even if it wasn't properly shown during Days and KH 2.
Not really, Naminé's role is actually pretty detached/independent from Kairi's apart from the initial premise in the plot of CoM where she starts the memory mess with Sora with his memories of her.
As with her role in the finale of Coded, Naminé actually stands on a
better foundation in the overall plot than Kairi herself does.
Namine is Kairi's Nobody but her role in the series mostly has nothing to do with her. I think Namine has had a very strong presence in the series so far despite her amount of screen time. I honestly love the character, she's not the most prominent when it comes to the spotlight but what scenes she does have always have a purpose. Her toilings all have a lasting impact on you, from instantly turning Repliku into a vegetable, prison-breaking Kairi, to subtler things like royally screwing over Roxas, the character just does the most with what she's given. It helps that she's a likeable character, she feels regret over the things she's done and her attempts at fixing her mistakes were meaningful and more importantly actually worked (granted at the expense of some other people).
You don't see people talking about Namine much but she's one of my favorite characters in the series, and imo the best female character hands down. Which is ironic since I hate Kairi's guts.
Correct, Naminé, despite her few screentime, has a better rounded character
and role in the overall series than Kairi herself has.
Her attempts to fix her mistakes are also not really over as fixing her first "mistake", while it indeed worked, caused only more regret and a new "mistake" made in her own view, which is surely also part of her being "still in torment" at present time.