It bothers me that he can behave this way in front of a bunch of black men. "You can't say that" seems like such a little kid way of handling things. That's something a mommy would say to her baby, or siblings would say to one another. At this point, don't even say "say it again". Either you walk out and don't return, or you handle him for his violent language towards you.
This is not a good look for black men.
Honestly, I think the word should only be used in company, but I'm not a person who grew up using that language. I do use it, but sparingly and personally. But if you are a person who uses it more freely, then fine, that's not the problem.
The issue is, that once someone has said it to you, you have to understand that you allowed that person to feel comfortable with it in a way that they shouldn't, even if you've never said it too them. I fell that black men are extremely open and friendly with too many people, leaving black people open to everyone. Yes, there are people who will say it to test you, not because you allowed it, but to test you, and those are the ones you really have to get at.
I've dropped many black friends over the years for allowing white women to speak like that in my presence, not theirs, but mine. I don't care if your friend disrespects you, but they can't do it to me, and since you allowed it, we can not be friends.
I can't tell men how to be men, but this ain't it. This is unattractive to black women who are serious and about our business. I find that black women don't deal with this as much as black men do. Is it because men test each other more, or because black women check white women at the door (a lot of us, not all). Sad story. They must be with white women acting like this.