The news is likely unexpected. Even if you saw it coming, it's nonetheless hard to take. Your spouse will be going away for a sizeable period of time, leaving you alone and vulnerable.
Chances are, your brain is a foggy nebulous of what if's and how to's. Long term, it's wise not to dwell on these things. But if you don't address them initially, you might find your worries becoming nagging, constant companions.
Separately, you and your spouse may want to put to paper all the reservations you're having. Brainstorm scenarios you fear, feelings you're experiencing and any other words or phrases that come to mind. Nothing is too silly or absurd to write down.
Not only is this process cleansing, but it serves as a great "talking points" list for the two of you to review together. (If you'd like, write this list in your journal. Review it after the separation is over to see how God met your needs and quelled your fears.)
Be sure to let your guard down before reviewing your spouse's list. Feelings are feelings; they're neither right nor wrong. Don't take anything on your spouse's list too personally. Instead, react with understanding and compassion. Bend over backwards to put your spouse's mind at ease.
The following questions might be at the forefront of your mind: