@Scytale Its mainly because most people see it as a "oh so now you care?" situation. the reality is he spent a year trying to get her out the room and she didnt give a fuck then. the dad could've tried harder but we see the story from his perspective and witness the hell of life sucking japanese work stopping him from doing so, she SHOULD be smart enough to realize the shit he grows through, but she doesnt see it like the viewer obviously will, where as we see the man is obviously falling apart
as for "repeatedly deveicing her" people dont really see that, cause we dont see from her perspective. and frankly that seems like a bit of an exaggeration. deceives implies he betrayed her or something, him going out with a girl doesnt do that at all. and (though i may be wrong) he only skipped out on like one or two "dinners" between the two of them. Now obviously him dating her "best friend" is a problem, but that still doesnt directly affect her in anyway, so he reaction feels a bit much (especially when she knows nothing about it, and is presuming the whole time). obviously he is seemingly going out with her "best friend" but do we ever get to see how close the two really are? do we ever see how much the daughter thinks of kisaragi as an amazing friend shes blessed about? are they really even "best friends?"
for one, i dont think miya knows anything about the shit her best friend goes through at home, and we established shes been locked up in her house for a whole year. have they talked much?
does miya care for kisaragi anywhere near as much as kisaragi cares for miya? does kisaragi even care? its hard to tell with her deceptive smile, their relationship is a bit of a mystery
Clearly neither the daughter or dad is completely in the right, and although the daughter has her reasons to be upset, we see from the dads perspectives, so obviously most things will feel justified. im sure if we saw from her perspective, most people would hate and thing the dad is creepy.
