You could have been my OH a few years ago writing this. Let me tell you something that have been mentioned above but i didn't read all responses.
When a woman is a mom, and in my case and maybe hers, a working mother.... many days I have nothing left physically or emotionally for sex.
My husband has figured out cook dinner sometimes, help me with house and kids, massage my back without the expectation of sex.. make time for date nights and do not talk about kids. That will be a solid start.
Best wishes on opening up positive communication. When my OH wines and nags for sex it is a massive turn off.