He needs help. Saying those things in front of a young child is just traumatizing and mean. Just not right. Thing is he needs a kick in the butt, something to light a fire under him to get him to get help. Maybe figure out a way for you and your son to take a break and let him think about what he's doing for a bit and let him know by no uncertain terms that you are going to do what's best for you and the boy. Especially the boy. You gotta do something before he gets worse. You don't have to leave the marriage, but try to kickstart some change in your husband if you really love him and know the good in him but as it is, the bad in him is overwhelming all the good.