Aren't those pretty standard symptoms for all of us? I definitely feel or have felt all of those.
You're going to get a bunch of different diagnoses. When there is no one answer there are going to be many answers. I hope that people can eventually surmise that there is one answer though for all of us that have overlapping symptoms.
If you've read my posts, I would say that symptoms are not exactly coming and going but coming to the surface and getting repressed, fluctuating back and forth across the repression point. The tone of your post implies that you've probably ruled out immediate, serious, physical possibilities? If so, I think you can feel confident in that.
I'm assuming your primary short term goal then is probably relieving symptoms and stress management should be a vital part of the plan. I feel for both of you but be careful projecting anxiety and stress on to him.