I ,ean I get what you're saying... but honestly, we all know what's wrong. Subin was just never in love with him. He stays with him because he sees what we see, that Jun is a good boyfriend and a good man. He probably wishes he could love him passionately, things would be so much easier. But the truth is that he doesn't. And yes, Jun deserves better, he deserves someone who will cherish him more than anyone else, but I've always known that wouldn't be Subin.
I don’t think it’s that easy. I think Subin loves Jin, it’s just not the explosive passionate kind of love and that’s fine. So far I feel like they both need to communicate more in season 2. Relationships loose their “spark“ after some time and that’s when you need to work together. Subins frustrations are ver well portrayed and realistic and so is Juns. I think the biggest no-go from Subins side is the threat of break-up, it’s just toxic behavior that harms both sides, as well as his weirdly unresolved feelings towards hyunwoo. Jun also has to work on his condescending way of talking to subin (I think the movie theatre scene was done very well since it is a realistic scenario that is quite common). I personally really hope they work on their relationship and that they stay together.
fck this story makes me feel so bad for jun i really really wish subin would start appreciating and treating him like the gem he is or he can fck off with that yellow haired turd