So, she's never been to rehab? She will learn some tools, get some good sober time in, but ... she still has to really want it.
My son went to rehab and sober living last year and relapsed. He finished another rehab in January. He's been sober since then and he says this time he gets it and that he really has accepted that he is powerless over alcohol. That really seems to be key- they have to accept the powerless of it.
Unfortunately, sober he still has the same issues/personality that caused him to cope with life by drinking. Now he has to learn to cope sober. So, there are no quick miracles ... ;-)
Enjoy the break. I always said when he was in rehab were some of the best sleeps I'd had in years.