I don't think that "death" is the perfect word here - it typically describes a permanent state.
FWIW, what you describe ("temporary state of complete loss of personal purpose") is called "Sinnkrise" in German (crisis of meaning/purpose).
(And because not everybody might know: the comment references Kübler-Ross' five stages of grief (when confronted with a tragic outlook)¹: denial → anger → bargaining → depression → acceptance)