The clinical term for someone who is unable to show empathy for others or to discern a state of wellbeing from one of hardship is "psychopathy" or "antisocial personality disorder" (ASPD). These are both personality disorders characterized by a lack of empathy and difficulty understanding or caring about the emotions and experiences of others.
It's important to note that the term "psychopathy" is often used in a colloquial sense to refer to individuals who display traits of callousness, lack of empathy, and manipulative behavior. However, in clinical settings, the diagnosis would fall under the umbrella of antisocial personality disorder.
Individuals with ASPD may have difficulties forming and maintaining meaningful relationships, disregard for the rights and feelings of others, and a tendency to engage in impulsive and sometimes harmful behaviors. The diagnosis of ASPD requires a comprehensive evaluation by a qualified mental health professional to determine if the individual meets the specific criteria for this disorder. It is essential to approach such diagnoses with sensitivity and seek professional help for a thorough assessment and appropriate support.