The ideal Victorian woman was devoted, submissive, quiet, kind, and resisted temptation. She was lovely but not sexual. She was obedient.
Lizzie is willing to be the ideal Victorian "angel." She ignores the calls of temptation from the Goblin Market, and she tries to convince her sister to do the same. She's able to resist even when her sister isn't. She warns Laura to look away from the market. She warns her that it's dangerous. Laura, however, doesn't heed her warning.
Lizzie is the responsible guardian of the home. She's waiting there when Laura returns and warns her against staying out late. She illustrates her warnings with the memory of another girl who gave into temptation. It isn't enough, however, because Laura has already eaten the fruit.
Both girls are dedicated to the home. They take care of the house and the animals, they cook, they sew while speaking of modest things. They're exactly the kind of women that the Victorians would have appreciated—except that Laura's giving into temptation has led her astray and she's sick for the want of more fruit. She loses her beauty and starts neglecting the home.
Lizzie is devoted to her family. Though she can resist the Goblin Market, she still goes to it when that's the only way she can save Laura. She is so strong in the face of temptation—such an angel—that even when they try to force her to eat the fruit, she refuses.
Her strength and resistance are rewarded, and she is able to bring a cure home for Laura.