Cimorene

As with anything, I never say never with epithets. There are good times to use them.

Sometimes a character doesn't know the other character's name. In that case, something unobtrusive like "the man" or "the maid" is perfect, and there is, in fact, no other choice.

Sometimes using one conveys more than using their name would. If character A is angry with character B, it is entirely acceptable for him to refer to B in narrative as the cunt, the fucker, the bastard, etc.

If I sat around for a bit, I could probably think of other examples as well. but yes, most of the time epithets are horribly misused, break POV, and make the reader cringe in embarrassment when they're not laughing their head off. But there are times when you can and should use them.