The problem was that her soul was shattering during that "bitch fit" (which is what the red static in her internal thoughts was showing, even after all this time, it seems people don't take seriously her condition at that point, Ilya even said a couple days prior it was a miracle her personality wasn't overwritten). If, and there is a very slight if, since Saber and Sakura originally had a plan (they mention it since Alter says there was something where they'd have salvation, even if the result was death multiple times) to deal with the blackening and the current situation. It won't be happy, but there could be an end to things with Alter and Sakura's plan with the grail.