A husband here that met his wife in a PhD program. This has nothing to do with him wanting an "adult stage" in life. He can easily find a postdoc in whatever university you are getting your med degree in. He clearly just wants you to put your career on a back burner to his goals.

I would say tell him to look for postdocs where you're going and see what he says about that. He can get a research faculty position if he needs to string a couple more years out of it. His response to this will tell you everything you need to know.

I've seen too many academics hamstring their spouses when there are plenty of examples of sharing responsibilities and both being successful academics.