Your husband needs to make it super squeeky clear to dear old Mom that he will NOT tolerate her speaking about you in such nasty ways, Whether she is drinking or not, does not matter.

I do think your husband should have just handled the remarks she made right then and there and really was no reason to tell you about it.

Your husband needs to make it clear to her that she needs to be sober and be gracious to you for allowing her into you and your husbands "home" <~~ this is not sweeping anything under the rug , This is taking a stand .

If she misbehaves well then she can leave right then and not be welcomed back ever again.

Boundaries ! use them