It honestly all depends. When my mood swings kick in it makes a world of difference. During depressed phases I can go for quite a while without ever thinking about sex (so I'd be the one that had the lower sex drive), but during hypomanic episodes I generally have a constant desire for sex, to the point where we've spent entire long weekends in bed, only getting up to get food, feed the cats etc so that she's the one who'll say,"enough is enough".
When the manic depression isn't playing havoc with my moods, I'd say we're fairly evenly matched. Of course any stimulant use puts me immediately into a chemically induced hypomanic state...