Wheelchair-user Janice Martin claims she faces losing 25% of her housing benefit, around £33 per week, due to the so-called "bedroom tax" as she has two empty rooms in her home in Coatbridge, North Lanarkshire.
The 50-year-old grandmother said she had no idea how she would cope financially with the cut and that the only thing stopping her from taking her own life was the impact it would have on her two grandchildren, aged four and eight.
She is calling for the UK Government to scrap the plans or consider changes to take into account an individual's circumstances.
Ms Martin said: "Sometimes I have to choose between eating or heating, especially when it gets close to when my benefits are due. I sometimes go to bed at about 3.30pm so I'm warm under the covers and can put the heating off. If they cut my income, I've no idea how I'm going to survive."
Under reforms to the welfare system due in April, people with spare bedrooms will have their benefits cut to encourage them to downsize to smaller properties.
Ms Martin claims she needs her spare room for when her daughter stays over to care for her. She also said her health was failing and she may need a carer to stay over more often.
Prime Minister Cameron, responding to her MP Tom Clarke's question in Parliament yesterday, said the Government has put a £50 million fund in place to help people losing out.