Well, what you suggest has been going on for 3 years. I actually don't press the sex issue, and always listen to her and discuss what's bothering her. In fact, we discuss her issues just about every day. I always know exactly what the issue of the day is.
I do probably give off non-verbal signals, since she often makes a statement like "if you are feeling frisky, you can forget about it", even when I have said not a word. I am not making this up. For her to feel any less pressured, I'd need to get an apartment and live there.
I read your posts, seems like you know why you are not in the mood, whereas my wife either doesn't know or won't say, and is not inclined to talk about it anyway.