Questions about ghosts and spirits are often put in the mental disorder basket. But entities do facilitate personality fragmentation and they do tend to give people a dual nature as the compulsions and desires of the entity are superimposed onto the person's own desires. Sometimes these desires reinforce one another as in the case of addictions whereby a beer drinker who has a spirit entity attach at the pub thereafter becomes even more fixated on getting their next drink, or a heroine or ice junkie seems all that much more intent on scoring their next hit and seems all the more unable to let go of this addiction, even though their conscious mind may truly desire being clean.