After the Duchess of Berwick and Lady Agatha leave, the stage directions indicate that Parker closes the doors, which leaves Lady Windermere alone on stage for the first time since the play's opening. This opens the doors to her unbridled emotional responses to everything she has experienced and learned over the course of Act I so far, which she expresses at length in a soliloquy.
HOW horrible! I understand now what Lord Darlington meant by the imaginary instance of the couple not two years married. Oh! it can’t be true [...] No, it is some hideous mistake. Some silly scandal! He loves me! He loves me!
Speaking to herself, Lady Windermere grapples with the hints she received from Lord Darlington and the straightforward gossip she received from the Duchess. The audience traces the development of her inner conflict through the monologue. In the initial part of the soliloquy, she refuses to believe what she's heard. She is able to hold onto the conviction that it must be "some hideous mistake" and "some silly scandal," because she knows that her husband loves her. This conviction begins to waver, however. As she looks in her husband's bureau, hoping to have her faith backed up, the discovery of the private bank book concludes the soliloquy as she exclaims the following sentences: "Oh! it is true! it is true! How horrible!"
Lady Windermere's vacillation is sandwiched between two sets of "How horrible!" When she first speaks these two words, she is beginning to make sense of what she's just found out, while continuing to rely on her own inclinations. By the time she speaks the words a second time, her departure from these inclinations is sealed. This soliloquy, though melodramatic, offers a moving picture into a young woman's disillusionment. As her trust in her husband—which has never until this point wavered—begins to shake, her conception of the world comes crashing down.
At the start of Act III, Lady Windermere delivers another lengthy soliloquy. She evidently has mixed feelings about her decision to leave Lord Windermere. It seems like the hope of her husband running after her forms a significant part of her motivation for running off with Lord Darlington. Lady Windermere's ambivalence is communicated through contrast and simile:
Why doesn’t he come? This waiting is horrible. He should be here. Why is he not here, to wake by passionate words some fire within me? I am cold—cold as a loveless thing.
Mirroring her soliloquy in the first act, this soliloquy showcases her character development. The "he" she refers to in her first soliloquy is her husband Lord Windermere, whereas the "he" in this soliloquy is Lord Darlington. Although her worldview has been shattered, she remains her old self to a greater degree than she wants to; despite the decision she's made, she continues to love her husband and wants to be with him.
The melodramatic simile in which she compares herself to "a loveless thing" underlines her helplessness. In addition, the contrast between "fire" and "cold" shows her uncertainty. She creates distance between herself and Lord Darlington, by associating him with heat and fire and describing herself as having "chill hands and [an] icy heart." This shows that she doesn't actually feel any passion for Lord Darlington, as she requires his extravagant words to kindle her emotion. While she wants herself to want Lord Darlington, she wants even more to stay in her marriage.
Until Mrs. Erlynne appears on stage, Lady Windermere's intention goes back and forth. All of the outcomes she considers are negative. Removing and putting on her cloak repeatedly, she oscillates between the shame of returning to her husband and the shame of going off with Lord Darlington. This reflects the challenge of being a "good" woman, as conventional morality often puts women in a double bind.
