She's an enormous ki1ljoy.
In this episode Carrie basically picks a big fight with Doug cuz he didn't tell Deacon that his ex wants to get back together. Since she didn't get her way she mopes about it until spineless Doug breaks into Deacon's apartment. Carrie basically c0ckblocked Deacon out of smashing a British model, and yet Carrie's is fine with Deacon's ex sleeping with someone else.