You're not the only one. His behaviour and the way he treats his wife is straight up abusive and coercive. And his behaviour is supposedly forgiveable  or it's rationalised,  by him being  a "woe is me, I have no oustanding talents and I am the middle child" spoiled mummy's boy!?

I don't understand the existence the 2nd couple in the drama or what they're meant to represent. They are a ridiculous OTT stereotype of a toxic couple.  I started wondering if I am missing some kind of cultural context.  Do they 'represent' something in a broader sense?

This "couple" really doesnt make sense. When the main couple is so rational and healthy, the male lead is a feminist why would they show a trash man and even play down his actions? Who would want to see such a character? I wonder if they included him to make the male lead glow even more? Eventhough they should have put a toxic character into the plot bc the male lead is perfekt as he is without comparing him with trash...