So, I have this idea. A parasite (or tumor) that causes whoever it latches on to be unable to make any sort of connection with those he cares about- they can't see or hear him, lose all memory of him and can't gain any new ones, and if he touches them they only feel vague disgust. All other people can interact with him normally. If he starts caring for someone new, the same thing happens to them. The parasite feeds on his loneliness.
Is it any good, or just a dud?