Oh, Ms. Duck would be doing a Happy Dance right now.
Mab=Molly.
However with my reformed Mab/Murphy/Molly theory, there exists right now parallel worlds whereby 'our' Mab is historical Mab, Murphy, or Molly. So, her blinking is a reflection of one of these Mab's feeling the effects from Molly's utterances. There are causations and effects going off and our Mab, right then, is getting a feedback from some of the Mab's/herself in these parallel worlds. The Mab/Molly entities within the parallel worlds are giving this Mab a 'talking too' via the mantle. Molly's words are placing bindings on our Mab.
Our Mab now knows Molly WILL BE Mab in some 'shadow' if not this one if she is experiencing these bindings. She does after all, remain with him. And, I find it likely Mab will not stop considering alternatives just as Molly said, it isn't over.
"shadow' is a parallel world in future, past, present, or parallel via mortal choice.
For my theory, we need to observe if Murphy comes to a point in which she is placing 'bindings' on Mab.
Harry's talk with Murphy about a relationship together and setting sell together like the Titanic, full steam ahead. Murphy agreed.
There are others I've talked about before. Murphy often makes 'deals,' like telling Harry..."you will pay for this coffee." ETC
These deals almost sound as if there is a Mab overlaying Murphy or a genetic predisposition torward Murphy making deals.
These though are said without having Murphy with a "mantle" enforcing what is said is truth, but I think we may see in the end that some of Murphy's deals get enforced by Mab.