My biggest fear has been that she will call and say that everything between them is over and she just wants "us",etc. She has done this more than once and always returns to OW.
So you prepare now and face your biggest fear.
Lets say she calls to tell you this. You just let it go to VM. You listen to VM:
Her"Please call me"
How SHOULD you respond? Her words mean nothing right now.
I would wait. Wait for her to call again. Let her leave VM again. You listen to it. You wait.
Might have to repeat this several times.
At some point you can text her: "Just saw you called. Can't talk now, but text me if it is important"
Read the text. Wait. Give yourself enough time to respond to her logically (what you SHOULD DO), not emotionally (What you FEEL like).
"What is best for my kids is best for me" Amor Fati Link to quotes: https://www.divorcebusting.com/forums/ubbthreads.php?ubb=showflat&Number=2879712