A friend in Alanon is going thru the separation part of the divorce with her alcoholic husband. She does not have a supervised setup, and just last week told me about the empty beer cans under his car when she dropped off the kids (approx 10 and 6) for the scheduled visit. From what she says there have been several different girlfriends staying there over the last year or so, routine inattention to the dietary needs of one of the kids, and recently, the other has been foisted off on neighbors to do do the remote schoolwork. My friend is killing herself working 2 jobs, parenting those 2 kids who are great, giving them a stable home and not letting the homework and dietary needs slip. She got no cards or thanks on Mother's day, just a late reminder by text to one of the kids about it that night. She is not the only one I know getting pretty raw and disrespectful treatment because they are trying to do right by their kids. A few of us in my homegroup go around helping out the alanon single moms; fix things and so on- helping others in recovery frees me from fear and frustration on a daily basis.
My suggestion is be very disciplined about the terms of agreement with their mother, not to be punitive- but please don't get yourself stuck in a corner with an unrecovered semi-sober parent making the rules. Boundaries about what you will accept from her would not be out of place eg; cold shoulder or the anger about all the unfair things you're doing means this meeting over, please refer all questions to my lawyer.
Speaking as a codie in recovery, I certainly understand wanting the relationship to be stable and calm but from what I can see, with an addict or at least unrecovered sort-of abstinent one in play, things are stable and calm only when they are getting what they want. As was said to me by my alanon sponsor, if you want to see what someone is really like, tell them No. Prior to getting into recovery, No told to me would get me all kinds of wound up and aggravated. Now with 6yrs of intensive work in Alanon, its just kind of annoying and mostly I can let it go and get on with my business without getting spun up.
The old relationship with her is over, and will never be back. It may be that it never was what you thought it was.