@MsJinks That's brought up another point, just when exactly OP is going to be able to fit her regular self-care in: I was going on about some all-singing, all-dancing care programme and all this, but it does involve carving out a set routine, period of time and dedication: a few erratic runs and the odd treatment here and there won't achieve much.
One of the most unbelievable things about this whole affair is that, even in the immediate aftermath of her husband's departure, OP, somehow, still dragged herself to work and fulfilled her duties to her clients without missing a beat: that shows you the kind of person that she is, of course, but, even if her employers have cut her workload back, she still has to deal with a full schedule, involving travel as well, domestic responsibilities, keeping herself fed and watered, all the while dealing with all this horrible ongoing mess, and at constant risk at any point of these vicious interventions by her husband, with OW continuing to pull all the strings and spewing poison into his ear. OP needs a period of time, space and calm to kickstart any meaningful care programme and make basic alterations to her way of life.
OP, forgive me if I'm being impertinent, butting in or overstepping the mark, but does your employer not provide any paid leave at all? Could you not ask for a period of compassionate leave, I'm sure if they've been understanding thus far, they would understand the need for this. Would it be possible to get away for Christmas on one of those Continental package breaks, taking DD or a friend with you? And, of course, your husband sauntering round and then suddenly finding you gone - the more you react in ways he's not expecting, the more that throws him off track.