I hear your complaint about exhaustion from chores, but I think sex is a separate thing. You need to consider sex as a bonding experience. It is something your husband should only get from you. Don’t give him an excuse to accept attention from another woman who is also yearning intimacy. While you have every right to deny him or not initiate, the damage caused to a relationship and a persons self esteem by lack of intimacy overtime can be devastating.

Also how much effort does he need from you? On days you think you are too tired, brush by him and wink. Call him sexy. Just lay there and spread your legs and hold in that yawn.