My experience has been that antidepressants can help with the symptoms of a depressive episode (such as concentration problems, fatigue, persistent low mood, etc) but not stop other BPD symptoms such as impulsiveness, feeling empty, abandonment fears, intense emotional reactions, and stormy relationships. So antidepressants do work on depression symptoms for people with BPD but they don't solve all aspects of the BPD. Therefore you may find you feel a bit better on the antidepressants but still have BPD problems that you need therapy to help with.
Hope that makes sense,
James
Joined: 01-22-2013