Valerie Mmanthe Mampshika,[Bachelor of Arts in Psychology and English].
Loneliness can be defined universally as a human emotion that is both complex and unique to all the individuals.
Individuals are lonely for various reasons universally for certain events which have occured in their lives.For instance, a lonely child who struggles to make friends at school has different needs than a lonely older adult whose spouse has recently died.
Psychologists believe that loneliness is a state of mind in such a way that individuals choose to be empty,alone and unwanted by the rest of the world,and individuals who are lonely often crave human contact, but their state of mind makes it more uneasy to form connections with other people in society.
In addition to the previous paragraph psychologists suggested that loneliness is not necessarily about being alone. Instead, if you feel alone and isolated, then that is how loneliness plays into your state of mind.
Aspects which contribute to loneliness might be starting a new job,getting a divorce,or moving to a new place and individuals feel as if they need to isolate themselves until they feel comfortable in their new environments which are life changing,and lastly it has been mentioned that most introverts isolate themselves universally to avoid explaining certain issues which cannot change.
To close it off,I would personally advice other individuals to give others space when they need it,and they should not pressurise the lonely individuals to talk when they are not ready.