Well, since your husband let them in, make him deal with it. Next time they come by, have him say that you are depressed and that it upsets you that they won't leave you alone and they are not to come over again without making an appointment, then don't return their calls, ever. They might be more respectful of this since he is the "head of the house".
So today this happened...
Phoebe, i cannot add much to the comments already made, only that I wish we could save you all this pain and trouble somehow. We are made to sneak around and be careful of what we say like the offenders in the situation, while we are in fact the victims!
Hope everything works out!