Boyfriend traveling a lot

My boyfriend travels pretty often for his job, and everytime he goes I always get so so sad, I start crying like the night before!! So here I am bawling my eye out because he leaves to Washington in the morning.
I'm 21 weeks pregnant and I also don't have many friends so I'm always so sad when he leaves and bored :(
For any women that has a SO who travels a lot, how do you deal with it and also what do you do when they leave?