Kingdom Hearts II my Theory about xemnas with videos(embedded)

before I start I could be soooo wrong and theres afew thing that don't add up so I would love to here your theories to...videos embedded below

anyway this is just a theory but heres how I think it went...
the black haired man in the new secret ending is Xehanorts previous self > during that battle he somehow gained powers to avenge he's friends death(the frozen guy) but at a price - memory loss(and silver hair apparently) > thus after the battle (the now)Xehanort was found by Ansem and became his assistant > (I think he might already be a Nobody by Now cause he does not change appearance again like say Sora to Roxas but then his heartless would have never met Ansen so that can't be right?)> anyway I think he is really old and the girl ES he has down in his "room" is dead and gone. and he's experiment he talks about, was trying to find away to bring them back to life so he could get his memory(and eventually heart back)(maybe he succeeded and thats why roxas looks like the blond one in the secret vid...NOT that it is roxas but roxas is the only one he could be reincarnated as(cause of his connection to the key blade?)

>one more thing is he could have been trying to get his memory back in an experiment
with the blue haired girl ES but it all went wrong and instead he made himself into a nobody and a heartless(and it has the clothing of the bold guy cause thats what he saw as a hearless...the bold one did kill his friend(frozen blond haired kid)

one more point. I know its confirmed that the black haired man is a completely new character but is Roxas, Sora. or are they separate? so if it was Roxas in the 1st game and sora was introduced in the 2nd wouldn't sora be a completely new character?

now the videos(they might and might now support this you decide)

new Secret ending(I think this is the past and its just before the Black haired man becomes Xehanort)

Both and subbed( http://youtube.com/watch?v=9tTuccjLnHI )

normal( http://www.youtube.com/watch?v=dA5bf5jG2co )

A scene where xemnas remembers a a conversation with ansem and calls the blue haired girl "old friend" well the armor and keyblade anyway...

http://www.youtube.com/v/WO8vw-sACKY

And a scene where Zexion and Xaldin talk about Xemnas' past (making a few references to the secret ending) and talk about the "other friend" that someone else has(maybe Xehanorts heartless???)

http://www.youtube.com/v/jhZ3JuCA3eY

*embedded stuff did not work so I put links*