I about cried for you when I read this. My first marriage broke up because he wasn't interested anymore. Sometimes it may be good to go way back to remember what it was that first lit you both up about each other and try to recapture that. Other times it may take counseling by a mediator to find what the problem is, and overcome it. I know you're a very busy lady (from your profile), do the both of you need more time to reconnect? Would something like a weekend away together help? (I wish I had a magic wand to heal relationships that fade). Try to gently talk to him and find out, in depth, why he began to feel this way -- is there someone else, or do the both of you need time away from computers, TVs, phones, kids, etc? Then you also have to consider this, as hard as it may be -- would you both be better off moving on? If not, get alone with each other, talk, get to the heart of the problem -- keyword: Together. If he insists that it won't work after you have tried everything you can think of, you won't have to look back and say you didn't try. I wish you the best , I really do, and hope that something I said may be able to help you in some way. I will keep you in my prayers in this situation.
Moe
Moe