My husband and I have been together for 15 years. We are 30 years old. We started dating at age 15 and have never been apart. He has had the same tremendous sex drive for the past 15 years. We, too, were occasionally having problems with him wanting it more than I did. I finally realized that we needed to compromise to be happy. I would go along with his desires more often and he would allow me to sleep when tired without *****ing more often too.
So my advice for you would be to talk to him about it soon, preferably when you are both in a good mood. Tell him that you love him and want him and find him so sexy, but that sometimes you really need sleep as much as he really needs sex. Tell him that when he goes to the couch, it hurts you so much and makes you want it even less. Tell him that if he could just hold you until you fall asleep sometimes, it would mean the world to you and make you want him that much more when you are rested.
Good luck. Horny men are hard to reason with! (no pun intended, really!)