I am not sure if I am fully understanding the situation with the Witches Familiar. The Familiar stores the witches spells for what exact purpose? Is it like her spell book of sorts?
And also, if the familiar dies the witch can no longer cast? Or she can no longer prepare ANY of her spells?
Yes, the familiar is a spellbook of sorts. The witch must choose the spells to prepare after resting and then spend an hour communing with the familiar to finish the preparation. If the familiar dies the witch can cast the already prepared spells but cannot prepare any additional spells until a new familiar is secured. A new familiar may be secured a day later after conducting a ritual that costs 500gp per level of the witch. The new familiar starts with all 0-level spells and two spells of each level from which the witch was able to cast before losing the familiar.