Yes I think he is in hiding, kind of like Slughorn did at the begining of HPB. He knows what kind of trouble Voldemort can be with his powers. Remember him saying he did "great things, terrible, but great" in the first book, so I would not want to stick around either if possible. He probably would have known that he would be looked in on from Voldemort. He doens't want to risk it at all.