I have to agree with "Myviewpoint" on this one --
As hard as some may try as parents, it always ends up boiling down to free-will. You cannot tie your daughter down and force her to make good decisions. For some kids, you can't even teach them to make good decisions.
Perhaps she's acting out because she's certain she has a safety net to fall into? You may not be willing to take the child, but who knows what kind of support she may be expecting from you. I'd be willing to wager a guess that you've bailed her out of all kinds of her own doings.
Perhaps its time to make your position clear to her. I'm not saying have an intervention or anything, but perhaps letting her know that if it came down to her losing the kid, you wouldn't be willing to fill in for her. Even if it doesn't change anything, it'd probably be important for her to know.
Most importantly, don't believe for one second that her behavior has anything to do with your track record as a mother. She's an adult, and her behavior doesn't reflect on you any more than a stranger's would.
I suspect you're also well within your rights to share with her what you've just told us.
Best of luck! I'd love to hear how this one pans out!