While I'm reading this, the only thing I can really think is this: how much more interesting would this story be if Juvelian was actually the main character instead of a generic, self-insert, isekai protagonist? Oftentimes in these stories the other characters are flattened by the complete lack of connection between them and MC who is essentially characterless outside of knowing the future and being "indignant for the villainess". The feelings, the suspense, the romance, all of it just feels neutered by having the MC be from another world, like they exist on a higher plane puppeting around a doll for wish fulfillment. How much more angst would there be if the real Juvelian had to deal with the realization that she was abandoned, how much more intimate would the relationships be if someone who actually had consequences to deal with was the focus of the story? This is a girl who would have taken her own life and woken up in the past, how would she respond? Even better, what if she had survived the attempt, how would the story progress from a girl totally shattered and trapped in the chains of her own mistakes? Instead we have reverse-harem capture game, number two-thousand.
If this story had gone in the vein of "Actually, I was the real one", or simply continued from the suicide attempt, then I think it would have had all the makings of a classic webcomic.