His not sexual anymore? What could this mean.

My SO and I could get to see eachother on weekends due to him working out of town. He works in Construction. So his job is very tough on his body. He's very cuddly and givese hugs and kisses. But for the past month when he gets home he doesn't want sex. I even try to blow him but he just doesn't want it. I know sex isn't everything in a relationship but I need it I feel closer to him and feel satified. I don't want to bother him about it because he works so hard. What do I do.