Torvald and Krogstad are both impacted by societal expectations in this play. Torvald, as a result of his rather blind belief in the perspectives of his culture, becomes a subtle victimizer of his wife. Krogstad becomes the victim of an arbitrary yet profound prejudice current in his society.
Torvald demeans Nora's opinions and her identity by assuming that she possesses neither (or if she happens to possess them they have no value in his view).
Nora is forced to acknowledge that she has no identity separate from that of her husband. This parallels the reality of nineteenth-century Europe, where a wife was regarded as property rather than partner.
Torvald, in the end, also begins to recognize that Nora has the right to an identity of her own. However, his repeated condescension and use of pet names has taken its toll on his wife and she is forced to rebel.
For Krogstad, society does not empower or enable him. Instead, society considers him beyond reform, viewing him as "fallen" into dishonor.
...because he once displayed a lack of honor means that Krogstad is forever dishonored.
Krogstand once committed forgery and encounters extreme difficulty in his attempts to reform his reputation. He despairs of any reputable path to this reform and is driven to blackmail.
Importantly, for both of these men there is a moment when the social norms are exposed for what they are. Redemption, of a sort, follows.
Krogstad is effectively redeemed by Mrs. Linde, a professional who is also a caring woman. Torvald's eyes are opened to his small-minded views on gender and he is freed from his myopic perspective when Nora confronts him.