Spiritually spanking- is spanking an act of love, or abuse?

As with any other act, both partners need to be fully consenting. If one partner feels uncomfortable, then it's probably not going to work out very well. The husband's isn't necessarily a prude; he's a conscientious guy who's just not into it. The wife isn't abnormal; a kink is a kink, after all. Neither of them is "wrong". Sometimes, even the closest of people just aren't into the same thing.