It's hard not to like Kitty, even if she is a bit of a meanie.
As Laura Brown knows perfectly well, she and Kitty never would have been friends if they had gone to high school together (9.28). Whereas Laura was a solitary bookworm, Kitty, in high school,
[…] was one of several authoritative, aggressive, not quite beautiful girls so potent in their money and their athletic confidence they simply stood where they stood and insisted that the local notion of desirability be reconfigured to include them. Kitty and her friends—steady, solid, firm-featured, large-spirited, capable of deep loyalties and terrible cruelties—were the queens of the various festivals, the cheerleaders, the stars of the plays. (9.12)
In fact, Laura thinks that Kitty "would have snubbed her in high school, had they been the same age," and "[i]n another life, not very much unlike this one, they'd have been enemies" (9.25).
Now that they are both married women living in the same middle-class suburb, Kitty and Laura are on a more level playing field. It helps that Kitty's life, like Laura's, has turned out to be slightly less than what she'd hoped for. After marrying her high-school boyfriend, Ray, Kitty has had to watch him turn into a bit of a "drub" (9.31). Ray may also be living with undiagnosed PTSD, which to the people of Kitty and Laura's neighborhood simply looks like strange, unfortunate behavior. As the novel's narrator puts it:
Kitty has seemed, until this moment, like a figure of bright and tragic dignity—a woman standing by her man. So many of these men are not quite what they were (no one likes to talk about it); so many women live uncomplainingly with the quirks and silences, the fits of depression, the drinking. Kitty has seemed, simply, heroic. (9.68)
When Kitty visits Laura on a bright June morning, she comes with a favor to ask. As she tells Laura, her doctors have found some sort of growth in her uterus, and she needs to check into the hospital for a little while so that they can see what's up. Will Laura feed the dog while she's away?
Kitty's fear and Laura's compassionate sympathy soon lead to an unexpected moment of intimacy between the two women. Laura wraps Kitty up in a hug, and, after a few moments, Kitty turns her face up towards Laura's: "Kitty lifts her face, and their lips touch. They both know what they are doing. They rest their mouths, each on the other. They touch their lips together, but do not quite kiss" (9.78).
Afterwards, Kitty plays it all off like it was no big deal, and she leaves Laura feeling strange and uncomfortable, as if she has done something wrong. As the novel's narrator tells us, seeing through Laura's eyes:
Laura releases Kitty. She steps back. She has gone too far, they've both gone too far, but it is Kitty who's pulled away first. It is Kitty whose terrors have briefly propelled her, caused her to act strangely and desperately. Laura is the dark-eyed predator. Laura is the odd one, the foreigner, the one who can't be trusted. Laura and Kitty agree, silently, that this is true. (9.81)
Even though Kitty leaves Laura feeling like a perv, Laura can't help but fantasize about kissing Kitty again someday. Unfortunately, we will never know if Kitty does a little fantasizing of her own.