Yeah honestly, his character came off a bit like… i don’t know selfish? maybe it was just cause his family wanted Sahan to drop his life in korea just because Philip was depressed. I also didn’t read the novel but putting your whole entire mental health on another persons shoulders is insane especially when Sahan when through the same exact trauma Maybe i just didn’t get some parts bc i see a lot of people blaming Sahan when to me it’s honestly just not his responsibility.
I don’t know what people will think of the next chapter, but considering the story didn’t really go deep into Phillip's POV I don’t think it matters.
I still haven't read the novel and will do right after the last chapter next week, but to me it's more about how Sahan will take it. It's not that I'll be blaming any of them, because I agree with you that they don’t owe anything, it's that he'll feel guilty and think of the what ifs - would going made a difference anyway, because in the end what if he'd gonne and Phillip would still take his life? That's the thing, they feel depressed and almost always this is the outcome. So it's more about how Sahan will take it. And also, how he'll go forward with losing the other person who went through the same thing he did.

spoilers:
i read the spoilers and damn i kinda dont care about philip, i have no attachment to him whatsoever. i hate that i just KNOW some ppl in this comment section will actually think this is heegeon or sahan's fault. im sorry but philip is not sahan's responsibility, especially since he is also mentally unstable and went through the same trauma, i will be protecting sahan from ANY criticism. also why tf does a depressed suicidal person have access to a gun anyway, where tf is the security for this son of a bajillionaire, i blame them for neglect. anyways rip philip, you will be missed (but not by me)