The Jungian concept of the Libido, goes far beyond that of Freuds. Freud focused on bringing relief to the Hysterical. Jung was the first serious positive psychologist/psychiatrist. He believed he was searching for souls and helping to liberate and foster their full expression. Jung split with Freud for many reasons, but primarily because of Freuds limited view of the individual and the nature of the Libido. Not only the urge, drive, instinct or force that propelled humans to propagate, but the very force that urged all life to grow and express in all of its potential fullness. Jung was more and was an idealist and an uniter (right brain) Freud, more of an empirical materialist, and a separator (left brain).
When a person complains of no longer being interested in his Wife, Career, Path, etc., then one understands that his Life Force is withdrawn from the Object and that as a consequence the Object itself seems no longer attractive despite the fact that the Object itself has not fundamentally changed.
In the unaware individual, the causes of Libidinal or Life Force withdrawal are usually quite different and often the very opposite from those that the person himself offers in explanation for their behavior. When a person places an over-emphasis or an exaggerated interest upon an idea, person or a situation then we know there is too much Libido focus placed there and there will always be a corresponding depletion elsewhere. With no control of his Life Force he is unable to will his own intention or direct it in the way that his true self really needs.
When a man lives with his Ego-Consciousness firmly rooted in the external (The Norm), he has little control over his Life Force. His unconscious repressions hold sway over his decision making ability and he unwittingly allows them to control his own endowed power of intention and choice. The Life Force, unharnessed, now energizes the unknown or denied parts of the self held by the Shadow of unknowing in the unconscious. Until he embraces and begins to integrate his entire Psyche, conscious and unconscious, his Life Force will continue to affix its energy onto the wrong things. At a certain point in ones life, with enough time, wrong attachments and perceived failures he can lose faith and hope in himself. He has lost all sense of the Life Force and must now rely entirely on his own will, ego and repressions to cope in life.