Interview at an office where a former friend works

I am interviewing for a job where a former friend works... She was hired recently. We had a falling out in nursing school and later developed a somewhat comfortable tho distant working relationship in class... I have an interview where she now works (the company is a large physicians' group with many offices). I am sure she would rather have one of her pals there over me... I do not know if she would sabotage me, and am not sure if I should speak to it in an interview. It is plainly evident that we would know each other... And they might even ask her if she knows me... What should I do? Keep my mouth shut or speak professionally about the situation? Please help me decide how to proceed! I really want (need!) this job!