
I feel like the husband just had a lot of insecurities and the affair was just a consequence of this. Like, he liked the other woman, because she seemed helpless, so he could feel like the protector in the relationship. And since the MC is more independent and confident, he didn't feel like he was needed, or something like that.
╮( ̄▽ ̄)╭
Men that feel insecure with self-assured women are going to be trouble sooner or later, that is, if they don't learn how to deal with their baggage.
OMG I LOVE HER. I wouldn't mind her and her friends having a whole entire manga, instead of just a chapter. Social critique and feminist critique in a villainess manga, yes please!