This C + X + Affair = Disorder scenario doesn't mention any little letters. That would be children.
The ONLY reason to continue living together during a separation is strictly for financial purposes. Even then, a divorce action that involves betrayal will turn ugly-as-sin, without fail.
Before either of these..............contractors.........attempts any construction of bigger, better, and stronger houses, they EACH need to get some better training so that they'll have appropriate "materials" to access for their next respective projects - if you get my metaphorical gist.
Neither C or X has any hope of having a healthy relationship unless they each do some work to repair whatever was broken when they entered into this ill-fated union.