Cerebral palsy sufferer Lisa Munden and partner Brett Fage live in a two bedroom house in Essex.
They face paying more from housing benefit changes because, as a couple, they are expected to share a room.
The couple have applied for the extra money available to local authorities to help people with disabilities.
Speaking to Daybreak, Lisa said: "Because we are a couple it doesn't mean to say we sleep in the same room."
She added, "if you go in my bedroom now, it's full of pillows because when I go to bed I have to have pillows to hold me in that position, so even though it's a double bed, by the time he's put the pillows in, there isn't any room for him."
Ministers have been criticised for their approach to housing benefit reform, where even the smallest reductions can have a severe impact on the finances of the poorest people, MPs have said.
According to the Commons Public Accounts Committee, the Department for Work and Pensions (DWP) had made no attempt to assess what impact the changes would have on homelessness, rent levels and arrears.
A report from the Committee added that exemptions and discretionary payments are confusing, and no-one knows how badly claimants will be affected.
From April, if you claim housing benefit and live in what is classed as under occupied social housing, you will have to pay a "bedroom tax" if you want to stay in your home.