How do you know you're not alone?
You say you've got friends. Pah! Do you really think they are? Do they forgive you for little AND big things you've done? Do they really care about you, I mean, do they have esteem for you? That's not for sure -_-, I talk from experience.
You've got your family, huh? And when you're gonna move away a long time? Will they still care about your little things that bug your mind? No, because they also have their own problems.
Everybody's got more or less a feeling of loneliness, even if their life is almost fulfilled and happy as ever. You're not alone when you face loneliness and accept it entirely, then, your illness will be soothed and you'll know you've got the cards in hands and make what you want of your life.