I am glad it sounds like you are making progress. This is just the experience of one, so take it with a grain of salt. But I was with a woman with bpd for many years. She never would get into treatment, go to DBT, nothing. In fact, she resented the very notion of the diagnosis. She would laugh it off and then run along to the more superficial interests she felt comfortable with. Needless to say, she has done an enormous amount of psychological, financial, and personal damage to me. I have no idea what is going on between you two in the relationship. I sincerely hope he is open to the idea of getting some help and working with a therapist, DBT program, whatever. If he is not, there may, unfortunately, be some rough sledding ahead. I hope not! Best of luck to you!