Re: The Impossible Girl: Who IS Clara Oswin Oswald?!?
My guess is The Doctor is going to find more versions of Clara only for them to die. The Doctor becomes so grief stricken at loosing companion after companion that he finally turns mad. He tries all sorts of ways to revive her and somehow ends up creating so many duplicate copies of her all across space and time that he is eventually bound to bump into one sooner or later, which is what his younger self bumped into.
USS Sentinel, Luna Class (STO)