What does she want the land for? What benefit is she going to get out of ownership? What is so critically important to her that you have failed to grasp? How can you correct this?

A good guess would be she resents losing control over direction. Allowing anyone else control of the route automatically takes her back into her past to a occasion where someone giving directions let her down. Given the seriousness of her attitude there's more to it than this.

I don't know the answer. If you take the blame she will never forgive you so you have to be a little more subtle. I could make some suggestions but these would be futile if you cannot see her problem. If you can you might have some ideas yourself.

For example. If you presented her with having the first option to purchase at the market price this might alleviate her distress. Telling her this would only make matters worse. She would need to see it. I doubt it would work.