Taxes: I don't want to give my exhusband 1/2 of my refund

Is there any way that I can keep from having to give my exhusband 1/2 of my refund? He didn't live with me since April 2006 so I paid all of the mortgage payments, our son lived with me full time since he moved out. I have a huge refund because I made less, had more withheld, was able to deduct the mortgage interest and claim our son along w/being head of household. How is he entitled to any of that? Will I get into any trouble by doing that?

I have done taxes for about 3yrs now. As long as it's not stated in the divorce decre your OK. The law states that he has to reside in the home and pay half or more of the household expenses for the last six months of the year. I would go ahead and file.