“I stopped breathing for two minutes and died. Sometimes I wonder if this all isn’t some sort of mistake, if I should be dead. But if it isn’t a mistake I have to be here for a reason. But if there is a reason, I don’t know what that reason is.”
We will discover that having passed once thru the doors of death she came back changed, enhanced with someone else's spirit, memories or powers. Lyra's naming namely I think.