Why is Mrs. Mallard's marriage an oppression?

Mrs. Mallard's marriage is oppressive, it seems, for a couple reasons.
First, she does not truly love her husband. The narrator tells us that "she had loved him—sometimes. Often she had not." He had evidently loved her a great deal, a fact she acknowledges when she considers her new freedom, but she simply could and did not return that feeling in a consistent way. As a result, the relationship felt oppressive to her.
Further, Louise Mallard's relief that she can now enjoy "a long procession of years to come that would belong to her absolutely" provides a clue as to another reason her marriage might have felt oppressive. The narrator says that now, for her, "There would be no powerful will bending hers in that blind persistence with which men and women believe they have a right to impose a private will upon a fellow-creature." Although her husband has been kindly and loving, marriage in this time period (which we can narrow down to the end of the nineteenth century) entitled the husband to rule over the wife. Louise Mallard would not have had her own legal or social identity; rather, her identity would be subsumed under her husband's. Despite his love for her, knowing that she must always submit to him regardless of her own feelings seems to have caused her to feel oppressed by her marriage too.