Why? Because you don't like what he says and you're scared it might be true? That's why you're trying to find reasons for ditching him? Despite him trying to help you and talking with you on the phone? A few pages before you wrote about how intelligent he is?
Hope, I'm so glad you've finally found a good therapist who is able to help you. Please stay with him. If he hasn't asked about trauma, tell him about it! Your BPD can be caused by severe trauma it happens often. The symptoms are not "mistakes" to be ashamed of. It just does how much you've been hurt!
I myself don't like seeing all my symptoms in therapy. It's sometimes shocking to realize just how damaged we are. But that's the only way to find healing. Hope, I truly wish you get the healing you deserve! Please don't leave this doctor who can help you! Discuss the possibility of cptsd and bpd, or a combination of those and then focus on treating the symptoms. Please take this great opportunity to find relief!