today we’ve been chatting as normal, but I’m still hurt - not just at his actions, but also at his complete lack of appreciation for my point of view.

It's not over and don't let him act like it is. Although this may not be a relationship ending situation, it sounds like a "regrettable incident" -- a situation that if left unresolved, becomes a wedge between you and your partner.

You do not feel heard and validated. As you said, your boyfriend made the whole thing about his enjoyment in speaking his native language and completely ignored what he already knew were underlying issues with your boss. How often does he ignore your feelings when they get in the way of something he wants or enjoys?

Google "regrettable incident" and get some tips on how to articulate your feelings about this in the most constructive manner possible. If your boyfriend really won't meet you even half-way here, you have a bigger problem than this dinner.