Gone and Crabby

Why must not knowing the next time we see each other make him crabby? I know it's sad and not knowing is killing me too, but why make this time apart more miserable than it has to be? I don't get it.... I wish he missed me like I miss him... and expressed it the way I express it - with loving comments and a voice filled with longing. But not, I have to hear anger and frustration because I guess that's how he's dealing with this. :/