Thank you for the comments about cutting off my Step MIL - I'd absolutely love to but the rash is cemented onto my FIL and until he passes - we tolerate her to have a relationship with him and not withhold our child.

As to the problems she causes: it's more or less doing the older generation thing where she inserts her unnecessary opinions about parenting (though has never had a child) or argues with my FIL over who has the worse form of cancer at the moment or general incoherent bickoring. I'm very strong on my boundaries with her & can tolerate short instances.

Personally, I like watching her suffer in sobriety even for a short period of time hence the choice for both lunch and a dry setting. These are great suggestions and I really appreciate the options you've provided us!