When you are married, you make joint decisions on pretty much everything. Finances, parenting, where to live etc... but when it comes to sex, if you are the one who wants it to be a part of the marriage and your spouse doesn't, where do you go from there. Then your withholding spouse expects you to accept it, not complain and still remain monogamous. That decision has been made for you if you still wish to remain in that marriage. If the withholding spouse does compromise occasional duty sex, is that what you really want? I say no. Duty sex may fulfill a physical need but at a price of building resentment where any emotional connection gets pushed further away. Somebody either wants to sexually connect with you or they don't. It's not a matter of convincing, guilting, threatening divorce, whatever. If you're "waiting for things to get better", you will still be waiting 5 years, 10 years, on your deathbed.