@Simpleton: While that's how things do go down in reality, the criticism by
@ghostt is spot on. None of what you said, Simpleton, was an excuse for her behavior, and even Hime realized that. Credit goes to Hime for resisting the attempts of her "friend" to stoke the flames of Hime's nonexistent anger--she's the actual worst party in this, vicariously raging at Momota and handling something as delicate as someone else's relationship with the care of a sledgehammer. (She's not even that old, has a kid, has a husband, and still acts like a hardened misandrist feminist.) All it would have taken was for Momota to break out of the spell of love for a moment, realize that he was getting the short end of the stick in treatment between the two, and Hime would have lost what she truly valued--and the "friend" would suffer nothing at all, with family intact, ineffectually consoling Hime with likely the same misandry that got Hime there in the first place.
Speaking of Momota, I can see why he did what he did. He genuinely loves Hime, and cared so very much about her that he went right back to taking total responsibility after Kana's warning that women will irrationally remain in the grips of extreme anger even if they are in the wrong. He didn't want to lose her, and as such did what he could to assuage Hime's (perceived) anger; this--as I said--(d)evolved into conditioning himself to think he was guilty of a deep transgression, and had to properly make amends. Luckily for him, Hime isn't a bad girl--we see that in the conversation with the "friend". Had it been someone else (like the "friend"), he'd have gotten far worse; it'd be the first sign/step of an abusive relationship. Women do engage in that sort of behavior because--
generally--they are not capable of easily taking responsibility for their actions, nor does society expect them to (for that reason). It takes endurance of emotional discomfort to do so, and they are less capable of dealing with that than men are.
On a side note...the words of the "friend", and even Hime's immediate reaction to Momota's words (but more the former) evoked memories of how, today, men the world over (at least in the West) are expected to regard women as equal to them; enough will assert that women are in fact superior. If anyone wants to advance that sort of perspective as truth, they must hold women to the standards men must live by--women cannot receive a pass for this sort of irrational behavior.