It is very interesting about John bringing up the male libido. There must be something majorly going on in your H's head that is blocking his sexual drive towards you.
When I was with my girl friend last year, my libido was constantly there until the point where I stated figuring out that I needed to end the relationship. Then I just had no desire as my inner mind was in turmoil on how and when to break it off. I can even remember being shocked at myself for fibbing that I was too tired and wanted to sleep instead of going like a belt-fed motor.