Confused by ending of Rebirth

Heavy spoilers ahead, beware

>!I couldn't quite follow the death scene. I recall that in the OG, Cloud is overtaken for a moment and almost strikes Aerith himself, but in the end he snaps out of it only for Sephiroth to deliver the blow directly. Big moment for my young self, and I was eager to see how they'd handle it for Rebirth, but I was left more confused than anything.!<

>!What seems to happen in the end of Rebirth is that in one version of events, Cloud deflects the blade before it hits, and in another he does not deflect the blade and Aerith is struck, but we end up with two overlapping scenes where Aerith collapses in Cloud's arms, one in which she isn't obviously injured and one in which she is covered in blood.!<

What am I supposed to make of that? Can someone explain like I'm 5? Was it that >!Cloud was imagining the reality where he deflected the blade, and it was some kind of delusion in his mind that he was holding a version of Aerith that wasn't covered in blood? But when we see her bloodied, we are meant to understand that to be the 'true' version of events? Or are we seeing an alternate timeline where Cloud does really deflect the blade, but Aerith dies anyway because that was her fate?!<