After nearly 20 years of marriage, my physical desire for my wife is utterly insatiable. I have a stimulating, engaging job, but spend much of the day fantasising about her. Thankfully, I am satisfied most evenings when we make love passionately. I don’t want to be one of those men who sulks or manipulates in order to obtain sex, so I do my best to take it on the chin when it’s clearly off the table. I have restless days and nights when I know I’m becoming too demanding, and have to impose strict self-discipline. Luckily, my wife has a powerful sex drive, too, but sometimes she asks if I primarily love her for her body. In all honesty, I don’t know the answer. I never fantasise about other women or watch pornography; I find seductive images of my wife more arousing than any strangers online. I dread the onset of her period and probably track her cycle more closely than she does. When it comes, it can last a full, agonising week. The first night afterwards is sheer bliss. I have a few hobbies, but these often feel like filling time away from my true passion. I bitterly resent my job when it leaves me too exhausted for love-making. I am an otherwise temperate individual, but sometimes I wonder if I’m addicted to monogamous sex. Then again, there are worse addictions. • Each week, a reader tells us about their sex life. Want to share yours? Email sex@theguardian.com. All submissions are published anonymously, and subject to our terms and conditions. Comments on this piece are premoderated to ensure the discussion remains on the topics raised by the article. Please be aware that there may be a short delay in comments appearing on the site.