@Magdalene5 some people are just difficult, and very hard to please.
(Also he is mean. The bit where he says "I guess I am just being polite and not using the word 'disgusting'"... well, he totally *is* using the word. Jerk.)
You can contact AirBnB support and ask if they can remove the review. Hosts usually do not have a lot of luck in getting reviews like this removed, but it doesn't hurt to ask. Emphasize that all your other guests felt your house was very nice and comfortable and have given you stellar ratings.
Even if the review is not removed, it should quickly be buried as it is pushed down the list by all your other glowing reviews. As a guest, if I see that a listing has all terrific reviews and one terrible one, I figure that the problem was that one person, not the host or the listing.
Keep providing great value and service to your appreciative guests, and hopefully this incident will just become a forgotten footnote.