I think the difference is that Euihyun was fully awake at the time he intended to end his life together with his younger brother,while Dan was half asleep or sleep walking. He mumbled something like " he wants to go to the hospital to see grandma before something happens to her ",but Jk misunderstood it as Dan wanted to end his life
But Potatoe tells him that everyone, including JK, knows it wasn’t him and even encourages him to come back. So, personally, I don’t think he tried to end his life out of guilt but rather because he doesn’t want to be alone. He has no one except his granny (and I think her death is near), coupled with the puppy dying, a bad day at the hospital… it all might have just pushed him to want to end everything..
Yes, Potato told him about the spray incident and that jk knew it now,he should be relieved but . Dan will only be at ease if it was jk that will tell him that it was not his fault,and that he was sorry for accusing him easily. And yes,I agree that one factor of his suffering is loneliness. Aside from his granny,Dan is always thinking of jk and the times they were together. The night when they're having fun,Dan is thinking of jk. He's lonely without him
So Mingwa is pulling a low tide in twilight on us? I hope she also took note on how to write a redemption arc