I am sorry that you are having some physical anomaly. Just keep checking in with the MD. Stress is capable of all kinds of symptoms but let the MD tell you that one.
Are you eating and sleeping? At the beginning of my separation I pretty much ate very little and slept very little. It made it hard to get through the work day for me. Gradually in time, I got my appetite back and the sleep is still a struggle (but better).
I stuggled with the idea initially of how to communicate with my AH after the separation too for the reason you stated. We don't have kids together but we had bills in common (which are finally separated) and we work at the same place (our offices are next to each other). For the most part, I drew a line that we only talk at work when necessary and only about work related things. He has not stuck to that rule. I found that email was best. Recently we tried talking on the phone and it was just a nightmare. I not only get the head spinning thing, but I realized that every phone call has either been to hurt me or tell me I am wrong. Who wants to hear that one.
With the holidays I was out yesterday and ended up running back home. It is still an effort for me to alone but there are always people here to talk to on the forum or our chat room. People always make me laugh in there.