Call your bf to come over and right when he walks in, tackle him to the floor! Trust me, he may be shocked but I bet he would like the surprise! Men are very good at expressing love in a physical way and that isn't a bad thing, really. He may not understand or process the "emotional" or "talk it out" side, but the physical side he will get that.

My husband may not always be able to understand when I break down crying for no reason, but he gets that I need to be hugged very tightly for no reason. I always run up and just suddenly am hugging him, even if he's sitting and I"m standing. And, after being alone (like physically alone) for so long being an only child, dad at work all the time, and no mom, I tend to be very huggy with my husband and kids because I was so starved for contact for so long.