OhBrother

Hi all,
I've been reading the threads for a couple weeks now without posting, and like most people that find this site, I'm really struck by how similar other people's stories are to mine. I wish I'd found this even sooner!
No need to go into too much detail of my sister's story I guess, since its so much like all the others: troubled teenaged years, then 20s filled with the same sad stories of drugs, stealing, lying, lost friends, losing apartments, the late night calls for money, etc. She was never exactly a model citizen, but it was oxy and percs that really threw her life into a tailspin.
Knowing what a hellraiser she was growing up with her, I just always assumed her chaotic lifestyle was just her..and that eventually she'd just grow out of it. I'm the closest sibling to her, so over the years I've known more and also had her confide more than even my parents.
It wasn't until this past Xmas when she was arrested for forging oxy prescriptions that I clued in to what was really going on. I've been having a crash course in all of this ever since. A month after that she was arrested a second time for exactly the same thing.
Ever since then I thought she was on the right track. She has an incredibly patient and understanding bf who had his own issues in the past and wasn't immediately scared off (though he told me some hair raising stories of theft and lies), she got into a program with a doctor who deals both in the physical and mental issues of addiction, and when in her right mind is actually very good at her job and could go places. My parents, who have had the worst of all of this over the years, are tentatively hopeful and I try to keep her stumbles from them (I'm in the same city as her, they aren't).

Things have got a bit bad again the last month, and here is where my questions about supporting her come in. I got a sense things were going off the rails a bit over small things: not at work when I'd drop by, "lost purse" requiring urgent money, things like that. Then her bf called me and said the lying and missing work and thefts had started again. He was seriously thinking of starting to distance himself from this, which has been my biggest fear all along because he's the biggest source of stability in her life. Addiction aside, our family knows she is a handful so have always tried to help and support them.
I took her aside over thanksgiving weekend and said (without trying to hurl accusastions, which just gets her defensive) that her bf and I had real concerns with her behaviour lately and were afraid she was losing the progress she'd made. Though she did get tearful and defensive, she admitted she'd stopped seeing the doctor (couldn't keep up with the fees) and had taken "a few" of the percs or oxys again though "not like before". I told her I would take care of the outstanding doctor's fees, plus if she was willing to have me go with her I'd attend every weekly counselling session with her and split the ongoing costs.
She agreed to that (and the doctor is agreeable), but the doctor is away for next two weeks. Until then I'm trying to keep her on the rails. I'm calling often, have offered to help get her into my gym, went over for our own thanksgiving dinner, dropping by work to say hi (and relieved to find her there). I'm more optimistic than I was even a week ago, though its not all perfect (she took off somewhere tonight without calling her bf to let him know where she is).
From what I've read here, I know I can't "make" her get her act together, but I hope that I can add some supports (going to her meetings, getting her doing things like the gym, hiking, etc, and making her feel more involved in the family) that will help her help herself, and take some pressure off her bf.
I guess that was a long post, but there are no quick easy stories about addicts, are there?