They are a married couple with seven kids. She is dominate and he avoids and works around her dictatorship just like Hermione and Ron do in the epilogue. Whether or not they still "love" they have accommodated to each other and have a successful marriage that will last. Long time married people recognize the "hot buttons" and have learned over the years to avoid them. Neither Molly nor Arthur see any future for themselves outside their relationship. Old marriages have survived and learned to adapt from the initial rush of passion. Seven kids shows that they are still interested enough in each other to get in on in the bedroom.
Also remember the maxim that "A man should allow his wife to say what she likes so long as he can do what he likes."
It was said that if you gave a million monkeys typewriters and let them type for eternity, eventually they would reproduce the works of Shakespeare. Thanks to the internet, we now know this isn't true.