A male is said to be impotent if he is not able to physically and actively able to engage in s*x. What is impotency in the case of a female? She is only a passive partner. If she was not interested in wife and husband relationship why did she marry at all. Was it that she did not know the implication of marriage and wife-husband relationship? Did she think it was like children playing father and mother?
Have you or any of the relatives on your side conveyed her attitude to her parents or other close relatives? Her parents and her elder siblings, if any, also would be equally concerned about this problem. If she has female friends they can also talk to her and find out her exact problem. Also you can approach marriage counsellors. It is nearing one year since your marriage. You have not stated anything about attempts, if any, you have made to solve the problem.