This should help your situation. Please feel free to post any additional details or questions in the comment section.
From SuperUser Hal_Al:
"If this is merely a cost-sharing arrangement where the amount paid is below fair market rental, there would be no reportable income to you. If the “rent” amount is the fair market value or more, there is still some question as to whether you even have to report it, as it almost always comes out zero. Most people take the attitude that it is not income; it's just roommates sharing expenses and ignore it.
What you are NOT allowed to do, because it is your own home (you have "personal use") is claim a loss from this activity, to offset other income. Because of the "personal use rule", your deductions are limited to your income. Net effect ZERO."
