He doesn't say he loves me as much

Chloe
Little back story: we met online 10 months ago, talked for a while then started dating 7 months ago. Before and after that we would talk all the time when he didn't have work. He's military and stationed thousands of miles from me and his hometown where I go to school. He's been caring through that entire time and told me that he loves me after 4 months of being my bf then that would be something he told me whenever we said goodnight to each other which was most of them and tell each other that we loved them whenever it felt right. 
A month ago he came home on leave and we finally got to see each other in person. Things wilth him were better than I had hoped it would be. Met his family and they liked me along with me liking them. Some of my own personal quirks that have come up in conversations he remembered. Despite never physically interacting with each other before there were no awkward first date fumbles of seeing what works for us. -him being here felt like I was home even though I moved to this city a year and a half ago. It was so close to perfect. 
Then he had to go back. Now normally I get hit by the winter blues hard. Its knocked me down for weeks at a time and getting back on my feet seems like the hardest thing to do. When he was here it didn't hit like it normally did. But when he went back to his duty thise winter blues were me missing him more than I had before. 
Work got busy for him shortly after he got back there which I can understand. And I did tell him about my troublesome winter blues and kept him updated on how ive been doing. I knew that going back home after visiting my parents would be difficult because we spent a lot of time there so I asked him to call me so I wasn't alone. He did and it helped and he told me that he loves me twice when we said goodbye because he had work. 
I have noticed that he doesn't say that as much. He doesn't tell me that he misses me or that he loved me as much as he used to. We also just haven't been talking as much in general because of his work. But its been a while since I got a 'goodnight I love you' or random i miss/love you text. 
I give all this context to help give some insight on the relationship before asking this: should I worry that he's pulling away from me? It is just my winter blues combined with missing him so much that's causing this? Or something else?
Please I'm open to your opinions, I'm begging for them.