I've posted it somewhere before, but Lana Del Rey's ten-minute "Ride" video - especially the monologue at the beginning - is very descriptive of the BPD experience, at least for me.

"There's no use talking to people who have a home
They have no idea what it's like to seek safety in other people"
"I was always an unusual girl.
My mother told me I had a chameleon soul,
No moral compass pointing due North,
No fixed personality.
Just an inner indecisiveness that was as wide and as wavering as the ocean."
"I'm trying hard not to get into trouble,
But I've got a war in my mind"
"I'm tired of feeling like I'm f***ing crazy
I'm tired of driving 'til I see stars in my eyes
It's all I've got to keep myself sane, baby
So I just ride, I just ride"

And also, Plumb's "Cut", which I'm not going to post a link or lyrics to, because I think it can be really triggering, even though it's a great song.