Why do i only get attention when he wants ?

My husband only pays me attention when he wants ...he makes me feel so neglected...granted he works long hours and is tired ALL the time but every time i go near him, even to sit on the chair beside him he makes an excuse to escape!..I only want a little kiss and cuddle is that too much to ask!??...he says he loves me and i 'think' he does but IF he 'did' why doesn't he show he cares?...I feel unhappy with things as they are and feel i need more from a relationship than this, when i confront him about it he says, im over reacting and he's not THAT sort of person (meaning he's ignorant and uncaring in my opinion) i sometimes think he doesn't deserve my love and care...When he's in need of some relief though hes like a different person and he can't get enough of me..as soon as he's done, he reverts back to his caveman self....All thoughts appreciated on this...be honest!