When we first meet Amy - as a child - she is already disillusioned. She thinks she has figured out people and she doesn’t really trust that the Doctor will return for her.
And the Doctor does not make it better by being 12 years late. There she is, talking about her Raggedy Doctor with no one believing her. He promised her he’d be back in five minutes and now he is just another person who didn’t keep their word. And even as she goes travelling with the Doctor she still doesn’t believe that he wouldn’t abandon her. She is so sure that he would just leave her there to die, even putting on a brave face.
And that has absolutely changed in series 6. Whatever happens to her, she is certain that Rory and the Doctor will come for her, they have her absolute trust. Her changed circumstances - in this timeline she never lost her parents - likely play a role in this. However, it seems probable that at least one of her reasons is realising that she can depend on them.
Now, that doesn’t mean that she is passively sitting back. She still saves the Doctor and Rory in The Curse of the Black Spot, she still saves River during Let’s Kill Hitler. She’s still awesome in episodes like The Wedding of River Song or Dinosaurs on a Spaceship. We get to observe just how much initiative she can take if her hopes are disappointed again in The Girl Who Waited - and we see that even now some of her fears and issues can still creep back in Asylum of the Daleks.
But overall, she has learned.She has learned to trust, she has learned that she matters to other people, she has learned that at least two of the most important people in her life - Rory and the Doctor - won’t abandon her.
in england in 1803, three brothers- Christopher, David, and Matthew- reside in the estate “Gallifrey Park” as doctors. Christopher (Christopher Eccleston), the eldest, is married to Donna Noble (Catherine Tate), and is looking to inherit the fortune of their aging father. David (David Tennant), the second, is madly in love with the poor Rose Tyler (Billie Piper), but is seeking to find a richer bride. The last, Matthew (Matt Smith) has taken Miss River Song (Alex Kingston) as his wife. The three brothers work as doctors, sustaining off their family’s wealth, with Rory Williams (Arthur Darvill) as their accomplice and his wife Amelia (Karen Gillan). Along with Clara Oswald (Jenna Coleman) the neighbor, their cousin Jack Harkness (John Barrowman) and his sister Gwen Cooper (Eve Myles), the three brothers live a peaceful life.
Until the first day of June, 1803 when they receive a letter. It is written filled with threats, stating that the first of every month, one new member of Gallifrey Park will be killed. Signed by a mysterious name- “The Master”.
The group must figure out the Master, solving mysteries and saving those also affected by him…