Down in the dumps...it's this normal?

So my bf finally slept over Saturday night and it was amazing! He's an attentive lover and enjoyed all our quite time together. He even cooked me a delicious catfish dinner!

Now normally it takes me awhile to fall asleep even after taking zzzquil or meclizine to help me sleep but with him i was out in like 5 minutes, a miracle in and if itself. Last night (and I fear this night) was completely different. I tossed and turned and paced. He'll I even enjoyed a little solo action and it STILL took me forever to get some sleep.

All day at work I was fighting back tears knowing I was coming home to an empty apartment. Is this normal to feel sad after your bf goes back to his place? Am I just going crazy because of the lack of a warm body to talk to and lay beside?