You are trying to make a new life that is healthy and positive and reaches your potential. You know you can't do that with him. You know it.
The chances of a person with BPD having a healthy relationship are about zero
Yes. I agree. They haven't been able to before, and they won't in the future -not without help. The best they can hope for is some kind of dysfunctional, unspoken contract with someone: "you carry all my

#$, and I'll let you and punish you for not doing a good enough job."
These little things are going to keep popping up. Unfortunately we cannot totally avoid them. They might knock you down for a moment, but what is important is that you get back up and keep your eye on the goal ahead of you.
Think of it like riding on rails toward the promised land. Every little bomb they drop is going to tempt you to steer your car off the rails, to the left or to the right. It is going to tempt your eye to look away from the prize. And when you do, you run off the rails and crash and find yourself in the desert. But the closer you get to the promised land, to where you are headed, the more you will realize this and refuse to jump the rails. This isn't about never having feelings triggered by them ever again. This is about staying on the rails and following toward the promised land even when those feelings are triggered.