"I will always remember when the Doctor was me"
Moffat’s Women - Oswin Oswald
Oswin is a genius, so smart that the Daleks decided to convert her when the Alaska crashed at the Asylum. She proceeds to build her own little world in her mind, in which she is still shipwrecked among the Daleks, but carries on bravely, baking soufflés (with varying degrees of success) and sabotaging the planet’s systems. Oswin projects an air of self-confidence and flirtation, she’s always good for a quip and quick to make friends - but she still never loses sight of her own interests and goals.
Finding out the truth about what she had become is horrific. Nevertheless, the same girl who pursued her dreams to travel across the universe, who kept the Daleks out of her head for a year by nothing but strength of will even if it broke her, succeeds at holding on to her identity. Ultimately, Oswin values her humanity to the point where she sends the Doctor away and stays behind at the Asylum, fully knowing what would happen once she takes down the forcefield.
I regret to inform you, Captain Steven G. Rogers went missing behind enemy lines on the third aerial reconnaissance has proven unfruitful. As a result, I must declare Captain Rogers killed in action.