If I understand your question correctly, you are paying a friend rent for the use of her home and you want to know if she should claim the rent as income.
Yes, if you are renting her home for more than 14 days, then she should be claiming the rent as income. If you are paying full market value for renting her home as compared to similar properties in the area, then she can claim expenses against that income. If you are paying less than full market value, then she is renting it 'not for profit' but still must claim the income and her expenses would be limited to the amount of income.
Without knowing her tax situation, there is no way to know the impact it would have for her return.