As far as Cameron's 2 personalities, it's very simple. I think deep down, she really does love Chase but there's one thing stopping her from putting it out there. Fear. As someone who has been where she is (sort of), I can explain. She loved her husband. Probably more than life itself. And he was tragically ripped out of her life. So, ever since then, she's refused to allow herself to feel that kind of love for anyone else for fear that she will lose them, too. She doesn't want to go through that kind of pain again so she figures if she pretends not to love the person and something happens to take that person away, it won't hurt as much. This, of course is a farce. I didn't lose a husband but I have lost plenty of people who were very close to me (both my parents and 2 friends before I went off to college). So when I got to college, I only allowed myself to be friends with a handful of people (I think there were only about 10 people that I became friends with). The reason? Just like I think is going on with Cameron, I had convinced myself that if I allowed myself to care about someone, I would lose them just like I'd lost everyone else. I know now that it's not true. I know that you can't just stop yourself from loving someone and even if you do, you never stop caring. Therefore, if someone dies that you care about (big difference between caring and loving), it will still hurt just as badly.
Anyway, I think that's what's going on with Cameron. She's afraid to love him because she's afraid that if she does, she'll lose him just like she lost her husband and she can't go through that kind of pain again. So she decided it'll be easier to put a stop to it before anyone had to go through that pain. Especially her. It sounds selfish, I know, but if she's anything like I was, that's what's going on and I can kind of sympathize with her.