While my AH was in detox/rehab, we spoke very little to not at all. It depends on what type of program they're in, some allow phones and such at certain times, some not at all.
I find it a little disconcerting that the rehab has a "family night" but you're the only actual family member there? So who are the other people who show up? The fact that they told you her rehab is no one else's business seems a bit of a red flag too. I guess it depends on the context and way the message was delivered though. While it's true your wife must lead her own recovery, I don't think it's fair to just dismiss family's concerns either. It's natural to want to know about your loved ones, and there's less callous ways to tell people to give their loved ones space and autonomy. It strikes me that she may be feeding them an awful large helping of bs to turn their opinions against you and create that hostility. If possible I would do your best to keep and create records of all of your conversations.
Tbh, it sounds like she's white-knuckling her way through this, and holding onto her resentments of you. My experiences with my AH were a little different while in treatment because of reduced contact, but he definitely resented me for my attempts to help him. It's like he would flip a switch, and go from crying apologies to hateful screaming. When an addict is in the throes of their addiction, any attempts to help them is seen as an intrusion. You become the enemy, and it's very common for addicted partners to become distant, malicious, or even outright abusive to protect their addiction.
I think Trailmix calling recovery a selfish process is a good way to put it, but want to point out it's a different kind of selfishness from active addiction. Someone in recovery makes "selfish" choices that they need to protect their recovery, such as turning down invitations from friends to events that trigger them, missing things at home so they can attend meetings, focusing mental and emotional energy on introspection, etc. An addict makes "selfish" choices to fit their needs, no matter how much it hurts others, like your wife only calling family when she needs them to fetch something. Your wife isn't making difficult choices that increase her chances of success, she's taking advantage of loved ones to get things she wants.
I know it sounds biased to support your divorce proceedings since I'm going through them right now as well, but I do think it sounds like the correct choice for you and your children. Even just the holiday example shows it well: the idea of upcoming holidays around her fills you with dread. That tells you what you need to know at its most basic form. Why stay with someone when the thought of your future together creates such anxiety?
I know it's really hard. That feeling of your partner choosing alcohol over you time and time again is so crushing. The way they flip situations around to always be your fault is maddening. I can only imagine how much adding adultery to the mix makes those wounds deeper. I'm glad to hear your family has some exposure to therapy, I hope that keeps expanding. Support groups and forums like this are so helpful. Listening to other experiences and explaining your own often brings so much clarity.
Good luck with your divorce paperwork and your kids. I'm glad to see you posting here, even if the situation bringing you here sucks. You'll get through this one day at a time.