I think what also crushed Song Rik was the fact he was left behind once again. His mom had promised a happy life together but decided to leave him with his shitty father and live a happier life.
Now his friend who felt like family/brother and a second chance to happiness made the same promise. To run away together and be free from the adults who hurt them and become each other's support. They plan a whole life together, on where to life, to finance, and even getting a pet dog. Sing Rik thought they were still on the same page even after the party. So when he tells JH to run away and JH starts to reject the idea and defend his parents, Rik is taken back as the plan was to escape the hell they were in. They both hated their families so what's going on.
I also think JH telling him that they need to face reality broke Rik, as he's been living in his shitty reality his whole life. He only now begun to dream of a happier future because of JH. And now the person who made him believe in a better life is going back on his words, he feels as if JH had abandoned him.
Do I agree with what he does? No, but I understand where this is all coming from. Which I really enjoy as we usually don't get an understanding of why a character is acting out in other stories.
wow. It's amazing how even purposefully bullying someone has not made me frustrated and enraged yet. The author is really damn good at nuances. Song rik knows exactly what he's doing and why he's doing it, to be told that birth family is the 'real' family despite everything, without thinking about just how shitty song rik's dad is and how he could never think like that must've hurt exactly like what jinhyeong is feeling rn. They're rehashing their deepest hurt to each other and goddamn, that hurts.
The only thing that separates them is that jinhyeong did it unknowingly, and song rik isn't. However, hurt is hurt and the impact doesn't reduce just because of different intentions and ignorance so I get where song rik is coming from. A part of him probably also knows that jinhyeong didn't entirely mean it and he's also desperately clinging to his father as almost a last resort but still wants to hurt him because the words were just too much, Damn.
I really hope that after this manhwa is done, the author continues to produce more works, they're just really good.