I hate to say it but I think that's the big issue. The BO was hurt by your reaction, she wants you to be happy and excited for her. Now I know you want to be, and I understand your own "selfish" needs. We all have them. I think the best thing for you to do is to try to find a more local place to board your horse. You may even be able to find a work to board deal.Wrong.
The BO currently boards the horse for free. The BO rents the property and the OP stated there are issues with the property owners.
In the long run - The OP needs to suck up and deal. She is only looking at herself and her horse - not her friend and her parents - whom the issue impacts the most. Moving their whole home and family.
The BO asked a question and I am sure was shocked at the tears. I can see how she would see the tears as selfish behavior on the part of the OP.
As for you friend, make sure you tell her you are happy for her. She needs a better situation. I know you understand that and I also know why you are so hurt. An hour and a half is really far. Fourty minutes is far. I really do feel for you.:-(