How did you reassert the boundary about emergencies? I'm wondering if you were extremely clear and objective. If so, you would already know what to do, imo.
If I could make a suggestion, it would be this:
W, I am only going to communicate with you about emergencies to do with S. (note - boundary setting is about what you are going to do, not about what you want HER to do. She will, and can, continue to do what she is doing. How you respond is what you control.) So, W, if you call me I will not answer. If you text me what the emergency to do with S is, I will respond if it is in fact an emergency. If you do not text specifics, I will consider it not an emergency and will not respond.
That is what I would consider really clear. And that would inform you whether to respond to "I'm really sorry" texts (no, and don't give it a moment's thought) or to "call me" texts (no, because you are being ambushed with non-emergencies). or to "I want to know how S is doing" (no, because she knows how to reach S directly).
I agree she's trying to exert control over the situation, and any wishy washiness you exhibit is going to make your life more miserable.
I will leave it to the vets who know these types of situations, but yes, you should have an idea in your mind about what would constitute a change in W that she wants to reconcile and/or has dropped the OM completely. That is obviously complicated because you refuse to take her calls. However, you can be sure that in 4 days that has not happened. Take a specific amount of time, at a minimum, to get your space. 90 days sounds appropriate to me.
Adinva 51, S20, S18 M24 total 6/15/11-12/1/12 From IDLY to H moving out 9/15/15-3/7/17 From negotiating SA to final D at age 50 5/8/17-now: New relationship with an old friend __ Happiness is a warm puppy.