To me too it sounds as if your husband answered as he did because he didn't want to admit that he had been in the wrong. Many men would have made a compleletely unjustified remark like that if they were drunk. Had your husband been drinking?
However, there are a couple of other explanations.
What is considered acceptable, unacceptable or rude does differ very much from one family or group of people to another, so your husband could have been hurt by something that you never meant to be hurtful. This has happened between my husband and me more than once and took time to sort out.
You said that your son and DIL were present when your husband spoke so rudely to you. I gather that you quite rightly waited to challenge him until they were gone.
Could you not tell either your son or DIL what you have told us here and ask them to be honest and tell you if they have ever heard you speak unkindly or rudely to your husband?
If he was just lashing out at you, then they will be able to tell you that that is exactly what his remark was. If, on the other hand, you unintentionally have spoken less then nicely to him, you will be able to find out what he meant.
Either way, please do not let this escalate any further. To me, it isn't the kind of thing that should ever have been allowed to result in your neither speaking to each other, or sleeping together, unless of course it is the final straw that has broken the camel's back and you are intending to divorce.