I sold flowers. I didn’t sell myself. Now you’ve made a lady of me I’m not fit to sell anything else. I wish you’d left me where you found me.
During her argument with Higgins in Act 4, Eliza describes the predicament that her transformation has left her in. As Eliza asserts, at least when she was a flower girl she could sell flowers and support herself, but now as a lady the only object available for her to sell in society is her body, as her prospects are now inextricably tied to marriage. Eliza here acknowledges how becoming a lady has trapped her. Indeed, Higgins confirms this when he continues to suggest that she will find happiness through marriage. In this regard, the play highlights lack of agency for women in Victorian society, its emphasis on marriage, and the fact that, as Eliza says, marriage for a lady has the effect of stripping her of her freedom.
You shall remain so, Eliza, under the care of Mrs. Pearce. And you shall marry an officer in the Guards, with a beautiful moustache: the son of a marquis, who will disinherit him for marrying you, but will relent when he sees your beauty and goodness—
In Act 2, Higgins assures Eliza that she will remain a respectable woman after he is done with her transformation. As she currently is, both Higgins and Eliza agree that her prospects for marriage are slim to none. By the time Higgins is finished with Eliza, he tells her that she will have her pick of a spouse, and in this instance, specifically, Higgins suggests, that she will marry someone of nobility.
Oh bother! What? Marry, I suppose?
Higgins says these lines to his mother after she asks him if he knows what would make her happy. The expectation that the middle class marry is on prominent display in Higgins’ flippant response that his mother would like nothing more than to see him married. Higgins, however, makes it clear throughout the play that he is a lifelong bachelor and that he views the idea of marriage as a hindrance to his scholastic endeavors, illustrating the ways in which men, while nonetheless constrained by the limitations of middle class society, have the freedom to flout convention in a way women like Eliza, once she becomes a lady, do not.