Symbolism, Imagery, Allegory
Dawn is Luciente's daughter. She's barely in the book; she's not really a fleshed-out character. But she's important because Connie sees her as a substitute for, or symbol of, her own daughter Angelina, who was taken by her into the foster system. When Connie first sees Dawn, her "heart turned in her chest. Her heart sharpened like a dagger and stopped. 'Angelina!' she cried out […]" (7.117-118).
Tricky Author Doubling
Similarly, Gildina is only in one scene in the book; she's the woman in the evil future who has been made over by plastic surgery into "a cartoon of femininity" (15.4). But while she doesn't have a big role herself, she is pretty clearly supposed to make us think of Dolly. Like Gildina, Dolly makes money by having sex (in Dolly's case with lots of johns, in Gildina's, with her boyfriend, Cash).
Like Gildina, Dolly is on drugs. Like Gildina she's altered her body (the speed Dolly takes has made her lose weight). And like Gildina, Dolly is controlled and terrorized by one man or another—the future guard who shows up at Gildina's door, threatening violence, echoes the first scene of the novel, in which Geraldo appears to collect Dolly and beats Connie along the way.
One way to look at these links between characters is as a nifty authorial trick. The novel is drawing parallels, and when you get the parallels you can sit up and say, "Aha! I see what you're doing! You're letting me know about a symbol!"
So what is this symbol, exactly? These parallels underline the fact that the present dictates the future. If the present is determined by those in power, women will end up as caricatures of femininity, as anatomically bizarre (and dumbed-down) as Barbie dolls.
If, however, the present is altered by the less evilly powerful, the future has a chance to contain warmth and maternal feelings. Remember that, in the novel, it is the powers-that-be that are both directly and indirectly responsible for taking Angelina away from Connie. Firstly, they indirectly cause her to go mad with grief by experimenting on her hubby, Claud. Secondly, they directly remove Angelina from Connie… and Connie thinks that this is because she was poor and hit her child, rather than just hitting her child.
The Future is in Your Head
But the links also bring up again the question of whether Connie goes to the future or whether she just goes into her head. Is there really a Dawn, or is Dawn just one way for Connie to think about Angelina? Is there a Gildina, or is Connie simply thinking about Dolly?
Dawn and Gildina could be doubles, or they could be clues, subtly showing us that Connie is nuttier than a fruitcake.