Perhaps the following excerpt from my draft Introduction to Folklore (which I hope to e-publish later this year) will help answer your question. Your question borders on literary interpretation, and that's a subject I'm not prepared to address (which is not to say your interpretation is invalid). Here's the excerpt:

The Eastern European tradition of the walking dead has diffused into North American thanks to the literary and cinematic use of the Nosferatu, the vampire. This said, the idea of walking corpses cannot be regarded as entirely an eastern phenomenon: the animated dead also played an important role in medieval Icelandic sagas. Here, the aptrganga maður – the “after walking man” – was especially troublesome and required the bravery and strength of a great her to end its reign of terror. Chopping off the head of the corpse and pacing it between the body’s legs was one of the only ways to put these monsters to rest.

Throughout European peasant society, there was also a great deal of concern about determining when a person had “passed over.” In modern society, it may seem obvious that death occurs when the heart stops. Even today, however, the line between life and death can be vague, occasionally requiring a judicially-determined definition. And even this can become the subject of political squabbling. In the modern world, death can be defined as brain-dead, but then there can be a question of whether it is appropriate, ethical, or legal to “pull the plug.” In traditional European society, the line between life and death was far more ambiguous. A person still living by today’s standards could cross over into the domain of death because of a disease, immense old age, or because of a curse. A large catch of fish or some other extraordinary circumstance might also signal the transition even when dealing with a healthy, young person.

In the Icelandic sagas, these people were known as feigr, or “fated to die.” This is echoed in the archaic English word “fey” as in “he had a fey look about him.” In other words, the person was destined to die, and somehow the shadow of death had already descended over him even though his heart continued to beat. A person who had made this transition withdrew from normal society and activities, preparing to die. Society regarded the person as essentially dead.

In the same way, the dead could do almost as much as the living. Medieval stories tell of the dead walking, talking, eating, and having sex. Obviously, such occurrences were to be feared and there were many rituals and forms of magic intended to keep the dead in a peaceful quiet of eternal sleep. In contrast, there was also a wide variety of magical practices available for the brave few who would call upon the dead to do their bidding.