[Soji]

True, we do not have a clear explanation of ve's meltings.
But if you guys Reread about what happened before Eve's melt ,there are several indications that Cruz is probably one of the major causes for the situation Eve suffers.
We all agree that when Eve brought Cruz back to life she shared some of her Eden Cell with Cruz.
Also Eve received a strong shock from Disk's device in attemp to reactivate Cruz's heart.
During the pfzero Eve was probably weakened by the lack of some of her eden cell which led to the current situation, the interesting thing is if Cruz had not been brought to life in this way he would probaly die during the pfzero despite the kind hands of light.
Another thing I want to emphasize is, even now it took her a week before she starting to melt this also happened the first time and we saw this memory world(I think this information has not been distorted)and who came with the cure?
Of course Saten who was present during all these events over ... coincidence? I doubt very seriously as it has been shown to know exactly what would happen to Eve ,by bringing the treatment necessary to save Eve's life.
So the causes that led Eve to this situation are Cruz and pfzero or at least I think so with what we know so far.