Also, Woojin for years tried to be "in his place" as a friend. He pretty much gave everything up, although Jaeyi says its bc of his pride and that is a part of it, just how long do you expect someone to silently act like a supportive friend while the person he loved for almost all his life builds a family with someone else. While Jaeyi did leave everything too, it was a form of demonstartion that he was all in with Woojin but that is not how it works. Grand gestures of affection can be daunting bc the person doing it may not expect you to reciprocate something of similar scale but as a rule of thumb in society we are taught to give gifts that are similar if not equal in value. Woojin is now constantly thinking what he can do for Jaeyi, bc Jaeyi in his eyes is suffering from all sides bc of him and the easiest way to stop all that is Jaeyi just going back to what he did before choosing Woojin but at the same time it isn't what either of them wants. Woojin has gotten in the habit of keeping things and feelings from Jaeyi that would be inconvinient for him and its a hard pattern to break within a few months of living together.
Some of y'all need to work on understanding nuances. This is not black and white. They've both fucked up and we're seeing it as an overview, not as one character or the other.
Of course were gonna expect perfection, because most manhwa authors don't deal with the nitty gritty of a relationship. The author has written this realistically. Neither of them can read the other's mind or emotions so they're bound to be self absorbed in some capacity.
They're two very different people who deal with shit very differently, so no shit there's gonna be some clashing when stressors arise at the beginning of an already sensitive relationship