First things first -- if you disliked Chelsea in Off Limits, for quite a while in Setting Limits, you are going to dislike her too. But you will also get an explanation for some of her actions. Is she right? No, but there are reasons behind her behavior, and they are legitimate. Chelsea certainly had some over the top reactions, but she feels everything very deeply. She acts out because she wants to preserve what she feels and what she has; she holds tightly because she doesn't want to lose it. The other thing you'll learn is that she's harder on herself than anyone else could be (something we share, interestingly enough).
Second and probably most importantly, there is a lot of growth in being open about her feelings and fears for Chelsea in this book and while some of that comes from Shay and Lochlyn, the majority of it is because of Weston. Hooo boy, dominant, strong, sexy Weston! He doesn't take the brat behavior from Chelsea and he pushes her to be honest and open about what she is thinking and feeling. He knows her as well as she knows herself and sometimes knows what she's thinking before she says it -- hold onto that guy, Chels!! It's nice to see them get their chance!