I too agree with both WebGoji and Calpoe, what your husband is doing is wrong. He can make all the excuses and justification he wants, but so long as he doesn't obtain clear consent, he is violating you. It is possible that your subconscious has actually provided verbal consent (inferred from you saying that you talk while having sex while sleeping). But he KNOWS that this might not actually be YOU providing consent. As there is risk to attempting intercourse during sleeping periods, your husband should avoid any possible attempts when you are asleep. That's just common courtesy, especially for a married couple.