Fear
A short drabble.
This is, I suppose, a result of Mr. Eleven (whom I love very much, don't get the wrong impression) never mentioning his past.
What if he forgot her?
What if he just moved on and never thought about her again?
What if the Doctor just got another companion and never even mentioned her?
Rose didn't want that to happen.
She didn't want him to be talking with his companion and them ask him a question about his past, and him just ignore them. She wanted to be known, but not in a selfish way, in a way that told people he was capable of love.
But there was nothing she could do about it.
She couldn't remind him to not bottle things up anymore.
She couldn't hold his hand when he let everything out.
All she could do was hope he didn't forget.
Because the worst feeling in the world is the fear of being forgotten by someone you will never forget.