my cat (11 years old) loves licking me. all the bloody time, any exposed skin and he's there licking away. particularly first thing when I am still in bed his record being 20 minutes of solid licking. he rarely licks OH and if he does it is very briefly. I have only known him lick one other person (male friend) why does he do it ? funny old cat !
I hate to say this, but some cats are very, very attracted to sweat - it's the pheromones which some cats react to like cat nip and like to lick. Could it be that you're sweatier than your OH? [runs and hides]