What should I do my husband is treating me like dirt since he got back from Iraq.?

I spent a couple of weeks visiting while my husband arrived to Fort McCoy WI. He called me when he arrived and asked for me to come up and visit. He had been in Iraq since Aug 19,2008-June11,2008. Everything was fine visiting him. Then we get home he leaves with no warning. He has been gone since July 1st. Treats me like dirt and wont talk about anything. I need help on what to do. What should I do? He has turned into someone else.