@Polycell
If by "her later actions" you're referring to episodes 12 and 13, then my bit about seeing her and Umi as Honoka's mothers still holds up. She knew she had to go because the opportunity that she got was huge, but she didn't want to leave her "child" behind. I have 0 doubts about the fact that both Kotori and Umi love Honoka (and vice versa), but I don't see it as romantic and when I do try to imagine as romantic it just feels wrong.