So, basically, nothing I can say or do will prove anything to you. I could show you pictures of my Mac, now being used by my sister sitting beside me. I could show you the email that I had of it shipping to me. But none of that is relevant if you don't want to see it.
You could've grabbed a picture of any Mac off the internet, and said it's yours! How would we know? And the Email? FORGED!
The only way I'll believe you is if you invite me to your house to play with your alleged "Mac", then you give it to me so I can run various tests proving it's a real Mac (ain't gonna take none of that Hackintosh BS), and finally, you gotta give me a half liter of your blood.
...don't ask questions about that last one. It's best you don't know.