Perhaps he means that when he has you he has a sense of euphoria and that when he doesn�t he is on a �come down�. So the addiction is the sex and he needs that euphoric experience. I�m guessing you roll in the hay every time you meet.
You might well consider it a compliment on your performance, assuming you like to be judged and scored on that basis. The fact that he hasn�t fallen for you yet confirms that he is enjoying sex with you, but is holding out to see if he can have the wonderful sensation of love and sex combined either with you or someone else.