I'm not a fan of Lilly recounting so much in the beginning. In this case it feels a bit too much like she's trying to give the reader a summary of everything instead of just thinking about it herself. That may be something you should look out for in general. There have been several instances where I was wondering why a character is doing recounting in a way that just feels like he wants to give the reader a summary instead of having these thoughts really come naturally. Not sure though how common this stuff actually is in stories with first person views... It does take me out of the illusion a bit though, so I thought I'd mention it in case there's something valid to it.
Anyways, especially one part stood out for me:
However, things changed when the topic turned to my own relationship with Hisao. I had intended to express how poorly rushing into my own confession had turned out for me. Hanako's response, that my mistake was in not being careless enough, was...unexpected. In that moment, all the frustration I'd been feeling came to the surface, and I let a comment slip that I shouldn't have.
Immediately, I tried to apologize, but I couldn't find the right words.
This information seems rather redundant. Since Lilly is an established character your audience should be capable of understanding her actions, unless, of course, something happened that we don't know about; that however doesn't seem to be the case. Feels like she should have just shortly mentioned the conversation and how it made her feel overall and afterwards (dropping the phone etc. is actually new and important to know) instead of detailing some parts of it.
Now reading your notes you apparently felt like you needed to justify her behavior a bit more to Mirage but I'm not sure if this would even accomplish that. Again, apart from her continuous struggle to come closer to her family there's, in my opinion, little new that comes from Lilly's perspective of the call. So if he felt it was OOC back then, would that change here? I can't speak for him of course.
You yourself wrote it like that because you thought Lilly's reactions would be appropriate given the circumstances, something I personally can agree with and, as a reader, it's nice to actually have to work your brain a bit and put yourself in Lilly's position, seeing if you can empathize with her. That gets kinda retrospectively destroyed by having Lilly just straight out tell us again, especially when it's part of a summarization instead of e.g. part of a conversation with Akira.
Feels like you should have a bit more faith in yourself and your audience. Granted I understand that MIrage's words count quite a bit, though I also don't understand why Lilly's actions seem so clear cut OOC for him when the arguments you yourself, bhtooefr and I listed seemed reasonable to me.
That said, all in all just a minor issue for me and otherwise the last 3 chapters have been great. I think you did really well with the conversation between Lilly and Akira, seemed very fitting to their characterization. The phone conversation with HIsao was great too. Really tough that Lilly just realizes that yes, there was still a mutual feeling of love, they just both failed to clearly show it, thus causing all the mess. I guess I'm also interpreting this right that knowing this lights up her feelings again? Considering the "I love you..." thought near the end and what else indicators there are throughout.
In general you often leave just enough room to interpret and consider character behavior that makes it a joy to read because it requires some active thinking, maybe that's also why I'm especially unhappy when Lilly recounts her perspective on things a tad too detailed for my liking.