1. Autophobia is the dread of being alone, or isolated from others. It often surfaces when a person feels they are being ignored, or are unloved. It is sometimes associated with self-hatred. It can also be tied into a terror of being alone in a scary situation (such as being alone at home with intruders.)

2. Social anxiety is intense discomfort related to being around other people, and fearing negative judgement or evaluation. It is characterized by an intense fear of social embarrassment, negative criticism, shame, humiliation or being rejected. These lead to feelings of insecurity, and the powerful belief that the individual is basically inadequate.

3. Social isolation is an almost complete absence of contact with other human beings. Sometimes it’s imposed – although it may be chosen – and the impact on the person is usually negative. It can lead to feelings of loneliness, fear of being with others, or low self esteem. Over time, it can produce severe psychological damage.  

4. Schizoid personality disorder (SPD) is a personality disorder that must be diagnosed by a medical doctor or psychiatrist. It is characterized by a lack of interest in social relationships, a tendency towards a solitary lifestyle, secretiveness, emotional coldness, detachment, a lack of concern for the emotional needs of others and apathy. Many people with this diagnosis simultaneously demonstrate a rich, elaborate and exclusively internal fantasy world.