No, I would not recommend anyone besides a professional working with her. And, what helped you may not be what would be helpful for her.

The diagnosis isn't important. And BPD is about development and separating.
14 year olds face difficult times as they are moving away from childhood. It is a period of separating and becoming their own self. It can be stressful for them and for those they are very naturally and normally separating from. I've always thought that most teens would benefit from some help and support for their difficult times. Maybe some family therapy would be useful too.