I've shot down two companies in the past three days because they made it known during the recruitment that they expected more than 40 hours a week, sometimes well in excess of it.
It's always couched in some doublespeak about "ownership". Trust me, if I were owner or part-owner in the enterprise, I wouldn't mind. But I'm not.
People complain about entitlement attitudes among the young. They need to look at employers if they really want to see entitlement.
It sounds like your boss feels entitled to your time without taking an ownership stake in your professional development.