Well, if we're actually being serious here I'll mention that my weekly gaming group started 24.5 years ago and my wife of the last 17.5 years was and is still an active player in the game. (In fact, back in 1982 I originally invited her to join the group in the first place because the DM of her previous gaming group was privately propositioning her for favors in return for game perks, which she and I were both appalled at that. When she refused he scheduled a game without telling her and then killed off her character.)
In all that time I can say that neither she or I ever gave one another preferential treatment when we DM, nor would any of the other players stand for it if we did. We've also had a number of other couples in the group over the years who felt the same way. Once a couple joined where the guy did favor his fiance when he DM'ed and they didn't last long with the group as a result. If the DM isn't ethical, and doesn't treat all players fairly, then what's the point in playing?