I completely relate to that - I never leave the house, I have no real life friends. My mum gets upset and embarrassed by it too. I'm 21 though.
I have no idea of how to cope in the world. I've been stuck like this since I was 16. I finished school, then nothing!
But I know I can't go on living like this forever. It's just really difficult to actually do anything. In a way, I'm scared to get better, because, that will mean having to face reality, and feeling completely lost and overwhelmed. I mean, how do you go from nothing to even a fraction of normal? I really can't see it at all. :?
I'm sorry you're feeling lonely. *Hugs* You won't feel as lonely posting on here though, there are so many friendly people that can understand and relate.
Welcome to the forum.