I have a husband in the military too and I found the same thing while he was away and with his other love (although that relationship was brand new and I hadn't met her). I had obsessive thoughts too about what time it was there and what was going on.
Since he's been home (she moved to the same city too) I really don't think about it much when they're out together now. I just kind of get on with my life. I don't know if it's something that's come with time or something that's come from him being in the same city as me again. Sorry I don't have an answer for you, but I thought you should know that you're not alone in feeling the way you do.
Everything will be ok in the end. If it's not ok it's not the end.