loneliness
Solitude
Shyness
social anxiety
social anxiety disorder
social isolation
Autophobia
Individualism
Interpersonal relationship
loner
Pit of despair (animal experiments on isolation)
Schizoid personality disorder
/suto3/google.iconloneliness
image loneliness
define loneliness
wikipedia loneliness
weblio loneliness
kotobank loneliness
jisho loneliness