Here is some information that might be helpful for you.
https://ttlc.intuit.com/replies/4838699
If
you want to consider the amount received as rent, then it would be a
not-for-profit rental which is covered in IRS Publication 523 on page 16
- https://www.irs.gov/pub/irs-pdf/p527.pdf#page=16
"If
you do not rent your property to make a profit, you can deduct your
rental expenses only up to the amount of your rental income. You cannot
deduct a loss or carry forward to the next year any rental expenses that
are more than your rental income for the year."
Otherwise any amounts received from your room-mate is shared expenses and not reported on your federal tax return.
You
can still deduct the mortgage interest and property taxes as itemized
deductions on Schedule A of the tax return as the owner of the property.
