Welcome to our forum.
I think the most important thing here is that your partner call or text you (with the understanding that it'll just be a short call or text) at least once a day when he's away. If you've already told him that you need this, and he's said, "No," then you have a problem and will have to decide if it's a dealbreaker. If you haven't told him that you need this, then you should let him know.
I'm sure there will always be a little jealousy tugging at the edges, so use whatever distractions you have to their utmost ability to help you keep your mind on other things. Also you might want to consider asking him to go on an out-of-town vacation trip with you sometime.
Hope this helps,
Love means never having to say, "Put down that meat cleaver!"