When I was a HDM ( ) I would have differed from CeMar (in his hypothetical) in this regard. NO WAY would I admit to be worn out! EVER!! There's always SOMETHING you can do! My attitude would have been, "Come on, baby! Is that all you've got?"
If it was a size issue....Hmmm. All I can think of would be to ask as she approached the big O, "Am I big enough for you now?"
Cemar, your W sounds as if she's using counterfeit info to hide the real issues. Implying that you're not "big enough" for her is BS if she's not utilizing what you've got, IMO. And complaining about how much you want it when she's not willing to have sex at all is BS, too, IMHO.
BUT...if there is a way for you two to have sex and you're being unreasonable because you can't have it your way or on your terms (other than integrity issues) is BS, too. Only you know what's real there.