Dear Inbred in Mississippi,
Sibling rivalries are part of growing up, and they don't stop just because you married each other. I fear you truly haven't thought this separation through. What happens when you run into each other at the buffet line during your next family reunion? Are you just going to let him have that last scoop of potato salad and head for the exit?
What you need to do is join the Air Force, get a good dickin' from a few of the enlisted men and leave those waterhead kids of yours with their uncle-daddy. Start a new life, maybe move somewhere exotic - like Tupelo. Most importantly, you need to leave your brother-husband alone and try a guy from another family (preferably no closer than a 4th cousin).
Abby