Re: the Inlaws
WJ, I feel for you. This is such a difficult position for both you and your husband to be in. Ideally, your husband and his brothers need to reach an understanding, and then have a joint discussion with his parents. Is your husband willing to set any ground rules for how the household will be run.
Can you afford to hire someone to come in and clean the house once a week or every other week, just to do the heavier cleaning? What about using a laundry service for the sheets, towels, etc. Do they have a TV in their room? Either get them a tv or put one in your room, and leave when you need a break. When my in-laws were living with me I occasionally needed a break, so I would go to my room and watch television or leave the house for awhile. It may have been culturally insulting, but it certainly saved my sanity on more than one occasion.
The time has come and gone for your in-laws to be treated as guests. They need to pitch in and help out with the housework. This isn't Pakistan where you have servants to lighten the load. They are apparently in good health, so there is nothing wrong with letting them pick up some of the slack. I wish I had some better tips from you.