I can certainly understand how you feel that way especially with bad memories of your own families resurfacing.

Have you considered telling him that you were very uncomfortable and angry by the argument/their behavior in the office?

My pdoc and his wife have a similar work arrangement although they have other staff, too. It took me a few years to realize they were even married. They kept everything very professional and still do.

I hope that this works out for you in the best way possible. It's kind of like you're between a rock and a hard place. You're there for mental health care but your doctor is screaming at his wife. Fights happen - but the office is not the venue for it.

That said, we are all human. If he is helping you, then I'd clear the air and bring it up, or just let it go with the hopes of no further incidences. I'd do whichever is more comfortable for you. You could always asked to be referred out if the situation was just too over the top. Do what's best for you!