Not only is your anxiety running the show, but your hyper-focus on what he is or is not doing is running the show. Going dark doesn't mean you ignore him. Newcomers get this wrong all the time. Going dark means that you do not initiate contact. And you follow some very specific rules related to contact:
If he calls you, don't always answer. You don't want to be available to him all the time. When you do answer, listen and validate. And then be the one to end the call. "Sorry, I am busy, I need to go."
If he leaves a voicemail expressing needing to talk to you, then text him back: "Sorry, been busy. I will be available tonight at 7pm if you'd like to call then."
If he texts you, and the text is just informational: "Went to talk to the lawyer today, he said he will have papers to you to sign by the end of the week." then you do not answer the text. Period.
If he texts you a direct question, answer in your own time (not right away because remember, you are busy!), and then when you do answer in as few words as possible. Yes or no questions get yes or no answers.
So based on this, when do you call or text him first? The answer: NEVER
To answer this question: "Is there a way to deal with this; i.e., limit contact without giving the message you are no longer open for business?" the answer is that YOU DO WANT TO GIVE HIM THE MESSAGE THAT YOU ARE NO LONGER OPEN FOR BUSINESS! That is the only answer that will get through to him. Any other answer means that you are still there, hanging on for any crumbs you throws you, and are still his Plan B no matter what he says or does. That is an awful message to send. Sending the message that: "Ok, you asked for it. You wanted to be apart. Well you got it! I am moving on!" is the only message that might make him see what he stands to lose.
Grow a backbone. Be the strong person we all know you can be. Go dark according to the rules above. Remember what DR said about the "as if" attitude. Trust me, it works.
M(53), W(54),D(19) M-23, T-25 Bomb Drop - Dec.23, 2017 Ring and Piecing since March 2018