Hi Naive
Your concerns are the same as mine about the boozing, however the details of the plan include some form of random testing which she must be willing to submit to - most likely a breathalyzer. In terms of the "custody by default", here in South Africa there is no longer such thing as "custody" even though we still refer to the term. The correct term is "primary caregiver", most often the mother and "secondary caregiver", most often the dad. The laws have been revised in favour of the father which is excellent for a hands-on dad like myself, but bad news for absconding fathers. By law we have to draw up a parenting plan. This is a contract which sets the ground rules between us for who gets the kids when, who pays for what etc. These new laws are applicable to biological parents, regardless of marital status, so even if you go and make a woman pregnant, you are compelled to take responsibility for the child should she give birth.
In the probationary period post rehab she most certainly is not custodian by default, she's being assessed for fitness for such a role. And yes, it's pretty much zero tolerance. Indications that she's drinking will mean primary care reverts to me, that is the bottom line. A sober mom in the role of primary caregiver is what all of us are aiming and hoping for here. It's the blue-sky outcome.
However, in reality the following will probably happen. She'll delay booking in to rehab, citing endless reasons why she can't go now etc etc. This is where I've scored such a coup. Armed with the forensic psych's report, which would ordinarily happen only AFTER I formally contest the conditions of the divorce, I can apply to the state family advocate for primary care of the children, which I almost certainly will get. Therein lies the heart of this. She can no longer obfuscate, deny, belittle, poo-poo, undermine her addiction. There will be consequences. Serious ones.
I also have the peace of mind that, should she get custody, if she resumes her Amy Winehouse impersonations after that, I have legal recourse to gain primary caregiver status. She will have a documented, traceable history of alcohol abuse which just makes things so much easier for me should I sue for primary care.