Yeah but that was years ago, and in between they were just fine super close. For it to be valid the separation should've started right after not after all that. They were best friends how could he come to the conclusion he has now right now ?? Like is he stupid she literally spelled out everything to him chased him and clearly showed that she didn't even car about whatever he was imagining. And after ALL THAT he's still unable to get it ? Most probably he just sees how he feels from what he's imagining, in other words he's being egoist. Or you tryna say it's some selective trauma or whatshit, doesn't even exist. He's just a loser let's be honest

Idk about you but this situation can still have a traumatic impact on someone especially when the other person almost died like twice (getting hit by a car, falling down a flight of stairs). Idk about yall but mincheol's overthinking + his actions are reasonably explained through this chapter I mean HANEUL LITERALLY COULDVE DIED IF THE CAR DID NOT STOP OR IF HER HEAD FELL FIRST!! That's quite a lot for a teen to bear knowing that his action of pushing her away from him could've made that actually happen