I did this before with SSRI's and it was awful. I also went off of my SNRI in increments as directed by my psychiatrist and it was hell. I was very sick and my brain was scrambled. Everyone has different reactions to medicine, so it may not effect you as badly as it did to me. Or it may be worse.
Either way, stay safe and research your medicine. If you want to get off your medicine, the best way is waiting to get stable or to talk to a psychiatrist. For me, if I'm stable and clean for so long I can slowly decrease my meds and eventually get off of them. I'm not sure if it's the same with BPD so forgive me if i'm wrong.
Even then, there is nothing wrong with taking medications. It sucks, but if it helps you then there is nothing wrong with taking them. If it isn't helping you, the best way is to discuss and test different medicines with your provider.
sorry for the ramble xP. Stay safe out there!