Does he love his wife? I can’t recall a single sign of actual affection. A wife is just one more thing to check off the “list of things to have”, along with a house, a job and a son to carry on… Well, I don’t think Vernon knows what exactly. Probably some ill-defined set of Proper British Traditions. To be fair Petunia is using him in the exact same way for for precisely the same reason. And the money, of course.