You are so right. From someone that went through something similar and I lost not one but two best friends, I still can't move on.
We were friends from kindergarten the four of us had so many plans and dreams but only two are here and we two feel so awkward together, both of us blame ourselves because we made it but our friends not. Every time we meet is so silent that is killing me.. so is better when we avoid each other.. 5 years have passed and still we haven't made any progress..
He probably hates himself too, imagine the guilt of saving the person you love rather than your best friend? I qould more than likely hate myself and feel guilty for even thinking after they're gone, I probably still want to take the chance at being with her. God it qould eat at me forever
Guys imagine how traumatic it would have been to witness the person you love (she most probably loved Yoonjae) get hit by a truck in front of you. Die in front of you. Bleed in front of you. You were just in high school. That would be something you'll carry in your heart all the time. That would make you go crazy every time you see cherry blossoms where he so clearly died under. These memories stick. And it can be very painful. It'll make seeing anything related to that incident unbearable, including seeing Rowoon. (May even be PTSD.)
And Rowoon loved her (it was his POV in Chapter 0) and understands that. That's why it's painful for the both of them. It's heartwrenching.