shocking and horrifying the player is kind of the whole point of the game

I disagree on the "shocking" part here. DDLC is psychological horror. It does have shocking moments, like the end of Act 1, but this is not the main point. It is way more about relationships than about shock moments. Sadly discussing that part of the game (the later acts...) is massive spoiler territory, so I'll stop here.

The fact remains though, that it is a horror game, and if the end of Act 1 is already too much, then sorry, but it is only going to get worse. A lot worse. (Or, if you enjoy psychological horror: Better. A lot better.)