Unfortunately the email address itself is the unique identifier, just like your phone number, so changing it would mean you'd have to tell everyone your new address before they could contact you again. As changing the address and telling everyone is pretty much equal to creating a new account with a new address, Gmail's solution is that you sign up for a new address, then transfer you emails and contacts. There's no way of "changing" an address.
Also, it's umm.. not clever?.. to wave your email address around on the web - there are bots constantly scanning for addresses to be targeted with spam. I'd suggest that you edit the comment.