Loneliness. What is loneliness? It's a feeling when you feel lonely.
       You can be in a crowded room, but you may have the feeling that you are completely alone or that you are in a full house, but again the feeling is that one, the result is the same.
      Or you can actually be alone in the room and wait for someone to appear.
Someone likes to be alone. Someone likes when someone is around. But we can not all be alone for a long time.