J.F.
I had the same issue with my youngest daughter. She was nursing for comfort and I was essentially her "pacifier" It took some crying and some pulling away from her etc but she finally gave up trying. It is going to be a lot harder on you than it will be on her. Maybe introduce a new "sleeping friend" a teddy bear or stuffed animal she can snuggle at bedtime -- a special blankie or even a pacifier. It might take a week or 2 but she will get the hang on it and she will understand. I know it is very hard but you both need to let go:) It was very hard on me as I thought our youngest daughter would be the last child for us, but we were THANKFULLY blessed with a son too!!! :)