Being as mosquitoes use heat sensing to home in on supper, it might be that the one being eating alive has the higher body temp. In your case, your husband's darker skin might be absorbing more sunlight and causing his body temp. to be higher. With Claude she might be like I am.

I can usually draw them to me just by walking outside and the "boss" might not get any due to the fact she has a naturally lower body temp. average(96.8) whereas I have a slightly higher than normal(99.2) on average.

Whichever is the one not getting eaten alive could run around, do jumpingjacks, or any kind of exertion to raise a sweat and stand close to the other and see how fast the mosquitoes swarm, just to give the one they love a break! :-) lol

Regards,
Lobo-hotei
lobo