Well, the center of the bed between 2 humans does sound like the best place for a little dog!
However, if you husband does not appreciate the extra warmth and affection maybe you could just move your dog over to your side of the bed? It may take several attempts until he learns he is not welcome in the center. It is possible to retrain a dog but I think it may take some time to talk him out of that cozy spot!
Maybe you could give him a special blanket or pillow of his own to encourage him to stay where you want him.