Many movie stars have experienced the plague of stalking.
What is the psychology of stalking?
Stalking has been defined by Westrup (199

as a set of repetitive behaviors directed toward a target that perceives those behaviors as unwelcome and intrusive. As a consequence, victims of stalking experience fear for their safety
However, there are several Grey areas and overlap between infatuation, romantic love, and stalking
What is the psychology of this behaviour?
research suggests that half of one sample of stalkers had a disorder such as antisocial personality disorder, narcissistic personality disorder, or borderline personality disorder. Borderline is particularly prominent in women stalkers
Laws on stalking
The first U.S. law criminalizing stalking passed in 1990, and within two decades similar laws arose worldwide. The growing realization of the harm stalking causes also ignited an explosion of multidisciplinary scientific research aimed at defining it, understanding its pathology and developing prevention strategies.
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Personality traits as predictors
A similar effort documented links between stalking and level of personality pathology. Using data from a sample of about 1,500 adults aged 18 to 30, Dominick Gamache, a research psychologist at the University of Quebec at Trois-Rivières, and his colleagues found that for women, the most predictive trait was Deceitfulness, in which others are used as a means to an end, similar to the trait of Machiavellianism. Female stalkers, Gamache explains, pursue their own needs to have a relationship regardless of the wishes of the other person. Impulsivity, which can lead to violence, predicted stalking in both women and men in the study. For men, however, the most predictive trait was what Gamache and his colleagues called Unusual Beliefs and Experiences. Men may believe, for example, that persistent pursuit and bold gestures are romantic despite clear signals the victim wants nothing to do with them.
Deceitfulness for women? Hmmmm