Well, as you have disregarded the consensus answer from the other site you posted too, it sounds like you want to hear something different?
The problem is, you and he HAVE grown apart. What you are wanting back is the way things were. You can not get back something like that. You had a wonderful relationship, but there have been changes.
And you tried to buy him back with a concert ticket.
He will go with you. And he might even try to have you in his life again out of gratitude. But he has still changed, there will still be problems, and YOU are the one hitting HIM.
Love does not insure a relationship will work. It does not insure a relationship will last, and just because you love someone, does not mean they return the feeling, or have it as strong as you do. And people fall out of love just as often as they fall in love.
You would be better off cutting all ties. Crying about it, eating some ice cream, and finding other friends to go to concerts with. The more you see him, the more you perpetuate the hope that you can go back to the way things were, but you said it yourself, he has changed. You can not have the relationship you had with a different person, and he is now a different person.
I would like to start by saying that no one is perfect. We all do things at times that when we come back and think about it five - ten years down the road, we're going to look back and think, "Really? Was that me? What on Earth was I thinking?!?"
After reading through what you've written, I think the best thing to do is talk openly and freely about your feelings with him. Somewhere quiet, and just the two of you - if you feel comfortable doing that. You should share with him how you feel, and ask for his honest feelings back. If he doesn't feel the same way about you that you feel about him, or if you feel that he is not being honest with you, then maybe it would be best to remain friends - at least for a while until you two get your lives sorted a bit more. It's better to always have a friend than to have messed that up by pushing for something more that just cannot be(at least at present).
If he's treating you poorly, or, as you put it "showing his true colors", then regardless of how infatuated you are with him, he's just not good for you. Love truly is blind, and I'm not putting you down, I speak from experience. Sometimes you just have to push that aside, and look for something better - and trust me, there are better things out there. Again though, this is something you'll have to talk to him about. I will add, that it's still not particularly nice to hit people - even if they deserve it.
As for the ticket situation, honesty is always, always, always the best policy. That's really all I have to say about that.
I'm not writing you off as being young, but speaking from experience, I can tell you that no matter how much you may love him, if you need to(not necessarily want to), you will be able to forget/move past/just become friends with him. Just remember that you have to do what you have to do, and that your parents and your true friends - even if they seem a bit distant at times - still love and care about you.
I hope this helps you in some way, and I hope you are able to get things sorted out.