If you look at the 180 section of DBing it says to do exactly that, a 180. If you normally start the conversations, stop. Be nice and answer his questions, but stop starting it. If you normally try to hang out at home, stop, smile when he gets there and happily announce you have something to do and leave the room, go do something that makes you relax, ESP in your own home.
You're right, don't let him treat you like you have a skin disease. Him moving to the other end.....that's childish.
A good buddy I found here explained something to me....sometimes they act like little kids having a silent fit because you told them no and now they want to pout. If one of your kids was acting this way, seemingly trying to hurt your feelings...what would you do? how would you handle it?