knr9311,
It's tough. It's real tough. I am in one right now. Married to her, it's tough.
You both have to talk. Talk about everything. You cannot risk not talking about it, that, whatever, it will crush the relationship. It's harsh words but it is truth.
You can't afford to lose the one thing you two have that brings you connection during those long stretched out days before you meet in person again.Talk it out.
You feel emotionally distant. This is completely normal. Our emotions get tired when they are stressed. And long distance is really stressing! Talk to your partner about this. It will not only replace the scare of silence with something it will lead to a discussion, resolution, connection and less stress.
It is okay to want to do your own thing, too, while trying to push the long days faster. We all need that. Yes, you'll need to let your partner know that you'll be doing such and such. If it is possible, let your partner know that they can contact you by different means (Skype, text, email, etc.). Don't push your partner away, be open.
Be strong in everything you do. Take everything as an experience.