Husband no sex

My husband has changed a bit lately, he's minimal affectionate, he says we should have more sex but doesn't get around doing it. I'm feeling very lonely and sad. We sit on the couch and he doesn't bother to cuddle and I seem to be the one initiating. I asked him what's the reason for him being so cold. He said he loves me but has a lot of work things on his mind. I'm not sure how that could effect being less loving to me, as if I'm not on his mind at all!

Despite telling him this nothing has changed. What can I do?