I think you need to ask him what the deal is? Sounds to me like the biggest problem is lack of real communication.
Just send him a link to your post, seems like you covered most of your concerns!!! Ok lol dont send him the link but just sit him down and have a nice heart to heart!!!
I can speak for myself but at age 42 I have been horny non-stop for 30 years and all male friends say the same thing, this leads me to believe there are some issues that you two need to get out into the open.
The thought of only making sweet lovin 1 time a month would have me so down in the dumps!
So good luck and let us know how the talk went.