In his essay on the uncanny, Freud explores the idea of the doppelgänger or twin. To Freud, the uncanny, the realm of haunted houses, the gothic, and the horror story—what makes us uneasy or "creeped out"—represents the return of our repressed thoughts. Our doppelgängers are the parts of ourselves we want to reject or can't allow ourselves to see. The main symbol of both the uncanny and the doppelgänger is our own corpse: we all know that one day we will each become a corpse, but that is piece of information we do our best to repress. because it is very unpleasant to contemplate.
In Freud, what is repressed always returns in other forms. Therefore, the creature could be understood as Victor's doppelgänger, representing everything in himself that he doesn't want to acknowledge. In this reading, Victor flees the creature precisely because he sees in it a mirror of his own monstrosity. The creature, in this case, enacts Victor's repressed fantasies, such as murdering Elizabeth, the new wife he might feel has been imposed on him by his parents, and his little brother William, a rival for his parents' love and attention. But at the same time the creature is doing what Victor secretly wants, the conscious Victor hides this reality from himself and is appalled, as he must be. His obsession with destroying the creature becomes, in this reading, the symbolic desire to destroy, rather than integrate, his darkest impulses.
This reading impacts the reader by providing a coherent and believable explanation for both Victor's rejection of and obsession with the creature.