Hey.
I recognize so much of myself in your general situation. I was like you growing up. Never really alone in the sense of not having people around, but never had someone to listen to ME. I still don't really have that, but I have found ways to cope with it. Remember you can't make everyone happy. The only thing you will accomplice is to break down yourself. You are the most important person in your life, make yourself happy, not to the cost of others, but don't let other take your happiness either. Let the one that owns the problem deal with it, don't take on problems that isn't yours.
It's not your responsibility how other persons choose to act in this world. Not with your dad, nor with your friend. I don't know what he is thinking, and I'd bet he doesn't either, but that doesn't give him the right to treat you with no respect. The least he should do is to talk to you about it, but if he doesn't, that is his fault and you can't take responsibilty for that. It's his loss. It's a terrible thing to loose your friend, but it would be a worse thing to loose yourself. The pain you feel is real and valid. You have to feel it to go on, but you can't let it get the better of you. Be sad, cry and scream over him (or even at him), you've earned that. Then keep it with you as an experience and go on with your life. You have a great life ahead of you. Don't let him define you as a reject, you are worth more than that.
We all long for warmth and contact with others. I'm sorry I can't offer anything more substantial then a cyberhug, but I care and feel free to write me if you need to tell someone.