To answer all three of your questions at once, I can't say for certain after meeting several of the young girls and even boys here. Some adults are useful in ways I never imagined they would be.

However, what I can tell you is in the iteration of the universe she's from, fighting Witches can be considered a hopeless engagement with no end in sight. How quickly a Puella Magi gives up hope and descends into despair is dependent on the girl's personality and emotional constitution.