Hi
Faith 
I think one of the hardest parts of having BPD has to be what it does to the person's ability to form healthy friendships and partnerships.
My DD is 30yrs. As so often BPD co-morbid, broad and wide. My DD (quiet borderline) is engaging, endearing, always been right out there socially, huge network of friends and life of the party. Everyone wanted a little bit of her DD was dx at 26 and through DBT she's reflected and continues to explore her role in her relationships. She let two unhealthy friendships go in 2016. She also told me she needed to sort herself out before any further romantic relationships. The great thing is her friends get her, understand mental illness, there is no stigma. When DD fell into crisis 2015, very ill her friends were there for her. Our home was an open house, they are her support group. DD also has support groups online, like we do here, it's critical as
Once Removed thankfully reminds us
Does your son share with you his loneliness, wants for a GF, splitting...…..
WDx