Casey did not complete HIGH SCHOOL. That is a major issue.
We don't really understand WHY she didn't finish high school (I have my
suspicions, but that is another thread).
Because she didn't finish high school....she couldn't get a decent job.
She felt worthy of a decent job..but employers aren't keen on people who don't
finish high school and for whatever reason she wouldn't get a GED (probably
self conscious about how having a GED makes one a "loser").
So...not only does she have the embarrassment of not graduating with her class, she can't get anything but a low wage job and THEN she gets pregnant too. She is so disturbed by this pregnancy thing she doesn't do anything about it..and finally Cindy catches on (in the 7th month!) and she proceeds to tell Casey what a screw up she is..etc etc.
Casey has a low paying job, no high school diploma, no steady boyfriend and her Mother INSISTS that she keep her "mistake".
From the age of when she should have graduated (17 or 18) to the age she is now (22) Casey has felt the normal natural urge to separate from her family. This is the job of all young adults..to separate from their parents. (Right, I know that she didn't deserve to separate from her parents, but she still likely wanted that). Certainly Casey saw all her young friends doing this and living on their own or with one another in roommate situations. The biggest trouble was that Casey was ill-equipped to support herself because she did not finish High School. The pregnancy that followed failing High School sealed her fate in the family as the "screw up". Young people who are very rebellious are doing the work of teenagers..they are doing their "job" of separating from their parents. Casey is no different than all young people in their desire to do this...but she had the extra feature of the baby that her Mother insisted that she keep.
Cindy "required" Casey to continue under Cindy's thumb..Cindy was so used to playing the martyr and "the boss", but Casey discovered how to be promiscuous and seized power in that way. The more Casey got tastes of "independent" living the more fed up she got with Cindy's rules. Casey didn't think that Cindy's rules should apply to her because she had moved into an "adult" world.
What Casey has over the Anthony's was:
1. (What they perceived as) the whereabouts of their Grandchild
2.
3. Youthful vigor and arrogance
4. A deep hatred (and give a **%t attitude) for her Mother (fueled by
the "requirement" to keep Caylee)