
okay, The first time I red this manga is all about hating the main couple(and I'm a bit sorry for that) specially the silver haired guy so I dropped this on chap 45 cause I felt the love chemistry of the main couple, and now I almost forgot the whole story, and I'm not really sure about what is the silver haired guys' reason for leaving kangwoo(if you guys know, I'll be real glad if you tell me) I'm sorry for being interested to kangwoo, so I might just skip and read his story. Yeah, I just really wanna know what is the silver haired guys' reason because I still(partly) hate him...

His reason for breaking up really came down to a lack of communication between both of them. And ofc this happens a lot in real life and I would think that the author did a great job of portraying their relationship realistically.
Hannie was always too scared of losing Kangwoo so he basically pushed himself and never voiced out his discomfort or his thoughts because he was scared that Kangwoo would leave him.
And Kangwoo wasn't totally blameless either, he thought the best way to take care of Hannie was to become better at his job, and to make sure no one treats Hannie wrong. He was a coward in his own way and this was one of the reasons why their relationship didn't work out. Whenever people suspect their relationship, Kangwoo just dismissed it by saying 'That's disgusting' which hurt Hannie. Ever since Kangwoo saw hannie beat up by his parents, he was scared to do anything that would make them stand out, or get treated badly and that involved not showing affections towards Han in public, which made Hannie feel inadequate, like Kangwoo didn't really love him. And if you read the story completely you'll see how through their 8 years of dating, Kangwoo never confessed his feelings to Jeonghwan.
So yeah...the break up was bound to happen and if I was in Jeonghwan's place I would have done it too. But yeah hope this made you hate him a little less, and understand him more lol
I literally fell for him all over again