How do you compartmentalize when in pain?

I am currently seeing two partners. My primary partner and I are having some struggles and have decided to de-escalate from primary. It has left me feeling emotionally raw. I haven’t seen my other partner recently, partly because it felt inappropriate to imagine going on a fun and fulfilling date while my other relationship is in such a difficult moment. It got to a point that I was entertaining the idea of ending things with my other partner because it felt like I was doing something wrong by still being with them while me and my primary were going through this. I realize that is an absolute poly no-no, and my primary would have never expected or asked for me to do that. I’m just struggling with carrying on as usual with my other partner during this time. I’m curious how some of you veterans deal with emotional disruptions like this. Do you communicate it to your other partners? Do you ask for space? Or do you just compartmentalize and keep it moving? Would love to hear some other perspectives.