When loneliness is your friend

There can be loneliness and there can be depression.What if a person is not addicted to any selfdestructive habits like drugs/sex/drinks etc?
Well it is a bad phase of life then.In a room all alone a man can always develop schizophrenia.It a disease when a man starts thinking there is a another world or another person around him.And he does all kinds of stuffs that are not imaginable by the normal guy.
I have seen a few films on people dealing with the same disease.And i felt that i could have been attacked by the disease because i also get lonely sometimes living all alone in my 4 storey building.