Things here are broader than the physical. Not for all people who are depressed, but a general absence of desire is common. It includes desire for physical things that you may have once liked or collected. Lack of desire for social things like friends or lovers or perhaps any contact with other people. Even the desire to be alive, which for most people is just a given, can be absent. I, for example, was not actually suicidal, I just had no desire to exist, but also no desire to put forth the effort to end my existence.