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If you own the house, you have the right to make her leave. However, there is a process. Even though she doesn't pay you rent in the traditional sense, the fact that she pays the electric and water bill would likely be considered as rent - entitling her to 30 days notice to vacate.
You need to give her a written notice to vacate in 30 days, and if she fails to do so, you can file an eviction action against her and get a court order removing her.