Kristin and Brody are walking on the beach when Brody reveals he and Jayde are on a break from their relationship. Brody tells Kristin he still loves Jayde but doesn't want to fight anymore. When Brody asks Kristin what she thinks he should do, she says he's more fun when Jayde isn't around. Kristin starts to reminisce with Brody about the good times they shared as a couple. Brody tells Kristin if they were to date again it might work out.Meanwhile, Heidi and Spencer are at home when Heidi starts dropping hints about her upcoming birthday. She tells Spencer she wants him to throw her a party at their house. Spencer is less than thrilled with the idea and complains that a party is a lot of work, but Heidi won't be refused.At Audrina's place, Lo is helping her fold some laundry. Audrina mentions she got an invitation for Heidi's birthday party. Although Lo says she can't make it, Audrina is thinking about making an appearance. When Lo wonders if Kristin will be there, Audrina says she's going to the party for Heidi -- not Kristin.Later, Kristin meets with Justin at a bar. When the two talk about attending Heidi's party, Justin says he doesn't want to run into Audrina, so he's staying away. Kristin says she doesn't want to see Audrina either, but she's going for Heidi and Spencer. Kristin assures Justin that Audrina won't be an issue, but Justin isn't convinced. He tells Kristin he wouldn't be surprised if Audrina tries to befriend her. Kristin asks Justin if there's a reason to worry about her getting friendly with Audrina. Justin says no, but Kristin asks if he's not telling her something. Justin again denies any secret keeping, so Kristin drops the conversation after saying she'll be honest with him if he's honest with her.The day of the birthday party, Heidi is getting the house ready while Spencer reads a book. Heidi asks Spencer which of his friends are coming to the party, and Spencer says Brody is coming with Kristin. He then asks Heidi if Audrina will flake on the party since Kristin will be there. Even though Heidi is optimistic that her birthday will allow Kristin and Audrina to put everything behind them, Spencer doesn't think any peacemaking will happen at the party.That night, Stephanie and Audrina are driving to Heidi and Spencer's house for the party. Audrina is excited to see the newlyweds' new home, but is less thrilled when Stephanie mentions Kristin will be there. Audrina tells a shocked Stephanie that she might tell Kristin she hung out with Justin the other night.Over at Heidi and Spencer's house, the birthday party is revving up. Kristin and Brody arrive in time to watch Spencer present Heidi with two puppies. Heidi is thrilled and tells Spencer she thinks they are the only babies she'll ever need.When Audrina and Stephanie arrive they give Heidi flowers. Audrina and Kristin don't speak, but Audrina grabs Brody for a chat outside. Brody tells Audrina about his break from Jayde and his renewed friendship with Kristin. Audrina tells Brody she doesn't know Kristin very well, but she doesn't think Kristin is looking for a relationship. She tells Brody that Kristin will have her fun with him to upset Jayde, then move onto the next guy.When Brody rejoins the party inside, Kristin asks him about his talk with Audrina. Brody says it was good because he hasn't talked to her in a long time. Inspired, Kristin suggests she talk to Audrina, too. She tells Brody that Audrina may hate her, but they should try to clear things up.Kristin pulls Audrina aside to tell her they shouldn't be ignoring each other, especially since they share the same friends. Although Audrina assures Kristin she's moved beyond everything, Kristin continues their chat. When Kristin says Audrina blowing off their lunch gave her the go-ahead to pursue Justin, Audrina tells Kristin she didn't go to their lunch because she doesn't know Kristin and didn't owe her a chance to talk. Audrina announces there's nothing left to talk about--she cared about Justin for four or five years, but now she wants distance from the situation. Kristin says Justin told her he was never officially with Audrina. "I know it must be hard for you to hear that as a woman," Kristin says. Audrina cuts Kristin off to tell her about grabbing drinks with Justin the other night. When Kristin asked what they talked about, Audrina says Justin also told her that he and Kristin were never together, and he never got over Audrina. The women exchange harsh words before Kristin rejoins the party and Audrina exits with Stephanie.Kristin is making breakfast the next day when Stacie comes over and asks about Heidi's party. Kristin tells Stacie about her fight with Audrina. Stacie is surprised when Kristin tells her she found out Audrina and Justin got together recently. Kristin says she feels like Justin has lied to her about everything, so she's meeting up with him for lunch to end things.At a restaurant that afternoon, Kristin confronts Justin about Audrina. Justin admits he talked with Audrina and grabbed a beer with her, but blames his problems with Kristin on their mutual distrust. Kristin says she's tried to trust him, but she moves on when she sees a bad pattern. Justin tells Kristin that she's pushing him away if her motive is to get a rise out of him. "I'm done" is Kristin's response. She walks out leaving Justin sitting alone at the table.