Disclaimer: I own neither Big Time Rush nor Cat on a Hot Tin Roof.
"Such a wonderful person to go to bed with, and I think mostly because you were really indifferent to it. Isn't that right?"
Tennessee Williams, Cat on a Hot Tin Roof
There is something wonderfully insincere about Logan. Everything he does is corny as if he knows he can't succeed and yet, at the same time, he knows he's so good he doesn't even need to try.
Logan's falseness is what attracted Camille to him (probably what attracted Mercedes, although with her its harder to say). Camille loves him and she hates him. She wants him to open up to her, to smile at her like he does with his friends. So far the only genuine emotion he's shown her, the only one she can be sure of, is shock (when she kissed him that first time).
Camille should never have tried to get Logan's attention, should never have kissed him, should never have tried to be his date to that party, should never have forgiven him for bringing another girl, should never have danced with him. She should never have asked him out, should never have agreed to be his girlfriend, because now she'll never leave him, and she should.
She feels trapped, just waiting to be burned. She feels like Maggie the cat (like she's on hot tin roof) and she knows how that story goes, over-wrought and desperate. She's just hanging on until Logan leaves her, or worse until he asks her to marry him (they've been dating for three years and people marry young in Hollywood). If that happens, it's just a matter of time until it all falls apart.
The band will fail (youthful dreams always do). Camille will sleep with Kendall (or Carlos or James, but probably Kendall). Logan will try to drink himself to death and so will Kendall (or Carlos or James). And they'll all be angry and petty and hateful and desperately trying to cling to past glory and to secure future prosperity and it will all be shit.
But Camille thinks that, hell, she isn't Hollywood's premier method actress for nothing and it's about damn time somebody did a remake of some Tennessee Williams. And so she hangs on to Logan just a little bit longer.