OK, so here is the thing my C helped me identify about why there is so much fear and anxiety here for me...

As my H has shared with me more about OW and her behavior, it seems very likely that she has a personality disorder and is capable of fairly extreme behaviors. It is very likely if H cuts off contact suddenly and dramatically, she will act out of spite, likely making things public. My H has a high profile job in which it is very likely he would lose it if this happens. This makes me fearful of two things: 1. what is she capable of and is my family potentially at risk? and 2. if H suddenly loses his job we are in immediate financial crisis.
Both of these fears impact my kids, and I can't tolerate that. If this was just about H and me it would be a diff. sitch.

This is where I feel stuck about demanding the zero contact boundary.

C encouraged me instead to start with a boundary around how much I can tolerate hearing about OW and "helping" H sorting this out. I can communicate the importance of ending contact asap, especially given her potential mental illness, but need to keep putting that back on H to figure out for himself. In the meantime, I maintain the boundaries already established which minimize (but don't eliminate) the cake eating.

I know it is not ideal, but I am really concerned about my kids here... make sense?