Don't give up hope! Maybe you should make communications very clear? Instead of timidly trying to iniate (after so many years of rejection even trying at all is an act of bravery) I ask straight up. "Do you think we could have sex tonight?" I usually get a pretty clear response. I'm not saying we have sex more because of asking but at least when she says no, its still less rejection than for me have to have tried to initiate physically.
The most important thing a father can do for his children is to love their mother.