Woowon's feeling is valid. Seo an feeling is valid. Both parties struggles with their father but in different situations. I cannot blame them for doing what they were doing. Their relationship have this sort of power imbalance in the 1st place.
Cutting off a family that's abusive to you is hard, I know that from a personal experience.
The author did a good job making both of them a complex character in different settings. This is like a miscommunication well done unlike those stupid ass manhwa where you could've just said something and no one gets hurt aka rape