Ok, I've reread the story quite carefully and I want to jump in. I want to outline the structure of the story and then focus in on the symbol of the two blue birds, because that i think is the key to the story. But I find it interesting how Lawrence builds to that and then the climax.
I see the structure of the story as dividing into five parts. The divisions may be arbitrary, but it helps me see how it progresses.
The first part is almost all exposition. From the beginning Lawrence recaps the relationship between husband and wife, how they could not live together, how she has "gallant affairs," how he works long hours dictating to his secretary, how the relationship with the secretary is platonic, and how he supports his wife. We get the impression of a very "modern," chic marriage.
The second part we have the wife disaffected and asks for the first time, "What's to be done?" Notice how this question keeps cropping up. But here she is asking about herself, and the answer is to head south for the winter to her gallant affairs. She's off like a bird and returns in the spring.
The third part she returns to find matters grown worse.
What exactly is the wife's problem? It seems that the husband is too comfortable. We get a dialogue between husband and wife over his comfort and his work:
She focuses on the discrepency between beiing happy and being comfortable. Obviously her greater value rests on happiness. We get some more bird analogy of him being a c**k with hens. And the wife concludes that she must do something:
And she wonders about what the secretary gets out of the relationship:
Part IV consists of what I call cognitive development, meaning we see the wife working out the issues in her mind. First she wonders what she herself wants of her husband:
Then she wonders what the secretary and her family (mother and sister) get out their adorning the husband:
Her mind gravitates to how his work has been damaged by these adorning women:
And finally this fourth section culminates in her decision to save him:
and
The fifth and final section is completely narrative, reaching the story's climax at a confrontation between wife and secretary. The wife steps outside into the spring day. Blooming flowers are described. She finds the husband outside dictating to the secretary. Two blue birds fly at the feet of the writer and secretary and engage into a bird fight. A dialogue between the three ensues, and the wife ultimately turns to the secretary to say, "Why don't you make him think about you?" This shocks everyone to silence. She asks him about his work and how it's declined. They have tea, and the women, the secretary now indignant, tries to be silent but the wife baits her into a fight. The wife has hit upon what is to be done, strike at the secretary:
And the secretary defends herself:
and
And finally the climax:
So everything through questions running through the mind of the wife builds to the confrontation. But what's that climax all about? As I see it, the two women fighting parallel the two birds fighting, and they (both dressed in blue) are fighting over the husband. But the parallel is also a contrast. The two blue birds are male, while the fighting humans are female. It's an inversion of nature. The women are fighting over a man, while presumably the birds are fighting over a female, or fighting in their normal natures. I think the story is a caustic satire on modern marriage and values. The people are not natural, but lead a sterile life. The wife's gallant affairs (men are supposed to be polygamous, not women), the husband's not having any passion, not even writing a novel but an essay on novels, and the secretary working herself passionless to the bone for someone. The birds serve as a contrasting image, ironically being referred to as tits:
The bird's gender is emphasized here, and the fighting tits are going to be the wife and the secretary.
