Can I just stand up for the woman here? Men- have you ever felt no desire whatsoever to have sex? Maybe you've heard someone has died, or you have just had sex and have no desire to have it again. The completely hormone-less feeling? If you can imagine that, and then add on feeling tired and stressed and fat and self-conscious. Imagine feeling like that, and then imagine someone reminds you that they haven't had sex for ages. How would you react?
Remember that a man's sex drive is (very generally) like a kettle- fast to heat up, fast to boil. A women's is more like an iron- very slow to heat up, slow to reach capacity heat and slow to cool down. They are very different bits of equipment.
I have experience of this situation, and for me I found the conversation nothing but annoying; I felt like I was a container that he needed access to, and he was put out that I would not put out! In truth, looking back, I had gained weight (a lot) and felt like crap about myself. Also he had changed- he was spending a lot of time with what I can only describe as a cult, and I felt distanced from him, but didn't want to complain, as it is up to him what he did in his free time. I DID still fancy him, I just didn't have any desire to have sex, and felt REALLY guilty about it. Him mentioning it just made it worse. So we split up. I felt like a piece of meat, that our friendship could become null and void if I didn't 'give' him sex. He even suggested he go elsewhere, which made me instantly lose respect for him. Looking back now (this was 20 years ago) I still don't think there is a solution. BUT gentle cajoling is not the way to go. Has your partner gained weight? Is there anything you have been doing that annoys her, or that could have made her lose respect for you? What's changed? It could be that the love hormones have just run out (read about oxytocin) and she has stopped fancying you, and that's that. It's tough. I wonder if there is anyone else on AB who has personal experience of this, and who got their sex life back on track after a break?