Could you have a functional relationship with a borderline personality disorder?

Yes: It can be challenging and there is a range of severity in borderline pd. I recommend dbt (dialective behavioral therapy)for bpd. Providing a stable caring relationship for someone with bpd can be very therapeutic.

Beyond : ...2learn that dr marsha linehan, respected psychologist credited w/developing new approach 4treating borderline personality disorder dubbed "dialectical behavior therapy" herself had been diagnosed w/bdp. Read her story via @nytimes http://nyti.Ms/yxtgz8 with expert help, it's possible 2develop strong sense of self & 2develop self-soothing skills + ability 2communicate feelings effectively.

Variability: I agree with my colleagues about the range of illness severity, and the helpfulness of dbt. If the person is committed to both self-acceptance and need for change, the storms in relatedness may gradually quiet. Without intensive therapy along w/dbt, the suffering inside the bpd person can be so intense that perceptions are very distorted, and the partner's emotional reserves are used up too.