Ohhhhhh can I sympathize with you!!
It has taken me years to get up the nerve to tell people that it just isnt a good time. I have a tendency to give 5 million reasons why its not a good time but I really dont think any of them are necessary.
I think its so rude of people to just assume that you want them to visit and you will be happy to entertain them. my inability to cook and my less then 0 desire to learn how kind of puts them off, thank goodness. LOL!