Can someone explain what happens in chapter 72

Which part exactly?

The flashback is from the time at the hospital after Shiwoo is held at Hyun's place, he just talks abit about how things are his fault and then glasses guy-friend (always forget his name) talks to Yujin about how last time this happened Shiwoo went abroad for a while, but this time he doesn't know what to do that'll help him recover..
Cut to present, Yujin talks to him again about similar things and then says he'll suggest to move and live together with Shiwoo.
Yujin then goes to Shiwoo and tells him exactly that, that they should move and live together! To which Shiwoo asks if Yujin plans to be with him forever? Yujin says of course! And then Shiwoo tells him that it would be better if Yujin finds someone else, someone who can make him happy (Shiwoo implies that he's burdening him instead of making him happy).

I hope that makes some sense :)

Thank u