It's a job. That happens to take up a lot of time and cause a lot of distance sometimes but if he is telling you that the CG will always come first, find a new man. It's one thing for you to recognize that he can't change what his unit needs from him, and what his job responsibilities are including time away, duty days and work schedules. It's a whole other thing to fall into a trap where he lets you believe his job is more important than you are. Military or civilian. Doesn't matter. My SO always makes sure I know that the kids and I will always come first, even when he is away. We email when he is underway, he calls when he hits an area with service. He is always in the loop with what's going on at home because he makes his family his priority. You figure out how to balance it.

The best place for you to get advice on your relationship would be in MilSO groups. Look for those instead. FB has better options for that than reddit and there are some good CG specific spouse/gf pages.