Add to this that we're dealing with Japan here, where "normal" rules supreme. From the start, even while struggling with her reaction towards men and trying to find love, the true focus for her has been on the need to fit in, to be "normal". While she's starting to realize that she can find some happiness being with Satou, she isn't really thinking any deeper about the reasons yet. Leaving the date to be with her was just her first real act of rebellion, breaking away from what's expected of her and following her own feelings, but it'll take more than this to fully realize the depth of them.
As beautiful as the moon is, the most important word is still missing from that line.