So the path belongs to you and you have registered a right of way there for the new owner? Did I understand that correctly?
If you have had the right of way registered for her all the way to the back of your property, then it's your own fault, then she is allowed to use the path like that and it is indeed a path and you are not allowed to park on it.
It would have been smarter to only register the right of way up to the height of her front door. Then the carport would have been illegally built and she would have had to drive over your private land to reach it - which she obviously is not allowed to do. And you could have used the path from the height of her front door to your place as you wished, since that is purely private land (which you use to reach your property, but which you may also use as you like).
Bad luck, I would say. The notary advised you poorly there. If the right of way had ended at the height of her front door, she would have had no other choice but to build the carport on the other side and could not complain if you park on your private land in any way you want (even if it is in front of her property).
If it is as I suspect above, then she has the right on her side and you can only be annoyed that you did not think it through properly back then and can be angry at the notary who did not advise you properly. But there is probably nothing more you can do.