Steve: Are you trying to protect her or him? Sounds like him. At 50, he knows the score. Not to put the horse before the cart, but successful May-December celebrity marriages include Harrison Ford/Calista Flockhart, Michael Douglas/Catherine Zeta-Jones, Joan Collins/Percy Gibson and Warren Beatty/Annette Bening.
Mia: I'd bring it up with her and ask her about her motives because you may find a side of her personality that icks you out more then the May-December romance.
Mia: Kindly suggest obedience school or ask to bond alone with Moose more often. But don't give her an ultimatum. A girl will always choose her pooch over your a man.