Boyfriend doesn't want sex

My bf and I have been together for a year and have had sex practically twice a day every day and I haven't gotten bored of it and the whole time I thought he was enjoying it too... Until today when he snapped at me and said sex twice a day is too much and he "needs to give his dick a break" what does that even mean??? I thought he enjoyed it and now he's saying he wants to do it once a day every now and again. Help :(