Ok, so I'm new to this fandom and I love this game. So I then decided to make a ton of theories about it, some of them suck, but some I tried to make sound coherent and somewhat good. So I decided to post this one and I hope you guys like it!
When Yuri kills herself and we spend the weekend with her, I don’t think that was all gibberish that she was talking about, I think she was trying to warn us about Monika, because there’s a lot of detail in what she’s been doing. And it does seem like Yuri knows some of it, because right when she confesses her feelings, she mentions that she doesn’t care if Monika can here them, which is another reason why she didn’t tell us that she cut herself, because Moinka didn’t want MC to know and try to help her stay alive, so therefore Monika programmed Yuri to become literally insane so that MC would feel uncomfortable around her.
Further reason why Monika is really sorry for killing all of the girls is explained by the poem “Save Me” in Act 2. The beginning talks about the “colors” Monika sees. Then she go’s on about saying how there was so much pain and suffering, and then she says that the poems are all meaningless. This is saying that she is tired of killing all of the girls and just wants everything to stop. Then it says, “Load Me.”