>>99655068Serenity is paying for Kim's car (albeit after she smashed it) and saved her from punishment. She still wants Derek, but it's pretty clear that she's not actively trying to steal him away anymore. Serenity actually improved.
But Kim just gets more jealous, openly hostile and vindictive. Serenity mostly reacts to Kim, while much of Kim's screentime is dedicated to her getting into fights with Derek, shit-talking Serenity, or thinking bad thoughts. She knows she's wrong, but unlike Serenity, she doesn't try to get over her problems or talk about them.