I am going through exact same thing. We are under the same roof and there are so many triggers. Shortly after BD, my W could not understand why I would get so upset when I would see OM or his car or something resembling his car etc... - goes with the whole "lack of remorse" thing. She never understood the hypervigilance and PTSD I experienced. At the time I told her when I was triggering. Now I have no one with whom to share this information, so I just suck it up and keep it to myself.
OM used to do our yard. Yesterday, new mulch was laid down. I can't help bust wonder if OM did it. Crazy, no?