Corri, I just had to jump in here and say that I think his approach is rude, also. I would not be turned on by such a request because his intent is not to turn you on or even ask nicely for something.
However, I'd have to agree with NOP and say that it's time for some building maintenance.
Look at it this way: To an HD person, saying "our sex life sucks" IS an attempt to stop the R from spiraling. No it is not packaged the way you prefer it, nor did he knock himself out to say it in a kind way but it is definitely an attempt at doing something about the R. In other words, he is feeling what you are feeling too (disconnected, unhappy, agitated) but he goes towards sex and physical touching as a repair and you go for quality time. I don't think his intent is bad but his approach could use some MAJOR tweaking. My gosh, did he go to the Beavis and Butthead School of Relationship Solving?
I would take his griping as a sign that he recognizes that the R is backsliding. As far as what to do about it...boy, that's a toughie. With him working so many hours and the boys' activities it doesn't leave a whole lot of time for Corri and Beavis to just chill out and enjoy each other, let alone factor in time for sex.
Anyway, I just wanted to say that he IS noticing the spiral and wants just as bad as you to reverse it.