Food And Sex
I had the same problem but mine and my wife's sex therapist proposed a simple, fun way to overcome it.
I bought a can of spray-on whipped cream, a bottle of Hershey's chocolate sauce, a bag of crushed almonds (other nuts work, too), and a jar of maraschino cherries (must be stem-on) from Walmart. Each time before eating my wife's pussy, I'd spray it with whipped cream, sprinkle on some nuts, drizzle on chocolate sauce with a back-and-forth hand motion, and add a cherry. Before I could eat her out, I had to eat up all the sweet deliciousness outside of her pussy, and periodically come up and kiss my wife so that she could taste it, too. Food and sex became inextricably linked, in the pleasure centers of my mind.
Now we can play pussy eating porn on the TV in our trailer while we eat TV dinners (our nightly meal), and it doesn't bother me at all.