Regarding family members/lovers/caregivers, the author probably:

Choices:
A. BPD is impossible to deal with.
B. not enough information
C. BPD should be avoided.
D. BPD is stressful to deal with.
BPD is stressful to deal with.
As someone diagnosed with bpd this question kinda tugged at my heart, for a few reasons.
From my understanding, the core of the disorder is an unstable sense of self and an inherent shame or worthlessness.
Before I was treated I thought I just needed someone else, the right person to come along to love me in just the right way, being mindful of trauma and never triggering my symptoms.
I was living in a fantasy world.
You cannot expect another person, a whole person with a sound mind and stable to sense of self to subject themselves to the circus act of our lives. We can't even manage it ourselves!!
I have been in two long-term relationships, and dozens of short ones six months or less. One of the two began when I was very low and lasted a very toxic 3 years. I entered treatment during that relationship, which resulted in it's demise. I was much happier afterward.
The second relationship began after I completed treatment. We have seperated twice during the past 2 and a half years, and our relationship is currently rocky as well. But who I am in the relationship has changed.
I am no longer the girl who needs extra reassurance daily that he's coming home from work. I can breathe when he goes to hang out with his friends. I am not threatened by every waking thought of his not being about me. Instead I am the woman that validates him and myself in arguments, and I put respect over everything. Of course I lose my temper. Self improvement is a constant process.
But, to avoid hurting anyone you love, you should definitely talk to a counselor if you are looking for another person to help you :) For family members/lovers/caregivers, it's stressful and often results in a lot of resentment in the relationship!
Be safe!