Nobody would ever write a book on the “dark” Zizek as, following in Lacan’s footsteps, he systematically highlights dark options and terminology. In contrast, Deleuze, like Jung, is both dark and bright.
The Shadow for Jung, but Deleuze too talks about the Shadow, is archetypal and not just a secondary formation, and God himself has a Shadow. For Deleuze the shadow is a gateway to becomings (becoming woman, animal, molecular, cosmic) and also the combat with the shadow as the only real struggle.
Zizek shares the Lacanian rejection of the “inner life”, which is quite worrisome, and for Lacanians who practice or who have been in analysis it is in bad faith. For Jung most of our “inner life” is outside, in primitive participation and also in what he calls the “psychoid” aspect of the archetype.
The hypothesis of the death drive may have had a biographical origin in Freud’s failures, as most of his concepts did, but it was no doubt also guided archetypally. James Hillman a post-Jungian analyst makes death and the underworld the major archetypes of the psyche and of analysis.
The shadow as personal complex can never be completely integrated because underlying it is the shadow as archetype. Integration is not the last word on the process of individuation as ego integration during the process of individuation must give way to integration in and by the self, which has a transpersonal composition.
“Inner” is a term rejected by Deleuze because of its dualist presuppositions and replaced by “intensity” but many intensities are located “within” us in familiar language. I see no reason to oppose Jungian and Lacanian perspectives as embodying absolute opposites of inner and outer, given that one tendency of Hillman’s psychology is to undo this dualism and to find, and produce,”soul in the world”. Some people usefully combine both of these perspectives, for example Ted Friedman: https://tedfriedman.com/centaur-manifesto/
I have always analysed Zizek (and before him Derrida) as representing a half-way house between Freud and Jung, and between Lacan and Deleuze, pouring old wine into new bottles, and thus as an unconscious Jungian.
I originally came to France in 1980 to get away from the Lacanian doxa that surrounded me. However, I don’t have any problem with making heuristic use of many concepts and images, a practice advocated by Deleuze and Guattari.
Zizek is not a seamless block, to be accepted or rejected in toto, but is a multiplicity that contains good aspects as well as bad, and is in becoming, like everyone else. I find the first chapter in LESS THAN NOTHING one of his most Deleuzian pieces, and it constitutes a tour de force in its synthesis of influences both named and unnamed (in particular Lyotard).
I would never re-read Jung as a prefiguration of Lacan, but I do take seriously the advice of Jungians who claim that only Jungians can understand Freud as they re-read him for the mythology.The same approach can be applied to Lacan and Zizek.
So I do not capitulate before Zizek’s texts but I propose a close reading that is at the same time a transformation. Reading is individuation, and I individuate both myself and the text I am reading by means of my process of interpretation as both Deleuze (who is a conscious Jungian) and Bernard Stiegler (another unconscious Jungian) have often emphasised.
Deleuze refuses the notion of constitutive lack because of its Lacanian and “priestly” associations. However his system is built on negativity (which is different to “negation”) as even a cursory look at his favourite prefixes (a-, de-, dis-, non-, in-) shows. He talks constantly not only of difference and deterritorialisation, but also of unmaking (dé-faire), a-signifying, de-territorialisation, disjunction, non-philosophy, in-nommable. He also talks about the fissure (“fêlure”) constitutive of the personality and of every event. He claims that deterritorialisation is primary, that it comes before territorialisation.
It is important not to fusion problematics but it is also important to find secret passages and unfamiliar resonances. Noone writes on Zizek or Laruelle from this perspective, and fewer Deleuzians than I would like practice it.
Note: I am indebted to a conversation with Andy Noobpwner for helping me clarify these points.