Husband coming home soon, what to expect and how to deal with it?

My husband deployed last July with the 5/2 Stryker Brigade from Fort Lewis, and his tour in Afghanistan is wrapping up. He is Infantry, and drives a Stryker, so I know he has probably seen and done some pretty "rough" things. He came home for R and R in March when our daughter was only 2 weeks old, and left when she was 4 weeks old. We are both new parents and when he was home he seemed very distant, like he didnt want to get too close to us. Does anyone have any tips or suggestions on what I should expect and how to deal with his homecoming?