This song is called Sleepwalking by A Fine Frenzy. I think it describes the lost feelings BPD usually brings along. I know for me this is true. Sometimes it feels like I'm looking for something and I can't find it, and I don't know what it is or how *to* find it. But I know that I'll be better once I have it. Sometimes this feeling makes me feel inspired, and sometimes it makes me feel hopeless. This song makes me feel a fine mix of both... Hope that makes sense

Houses to houses,
Sinks and walls and floors,
Windows to hallways,
Closed and open doors.

Softly,
They creep softly.
Lost, we
Now have lost these.

Cover your eyes with the paper clothes
That you stole from paper sheep.
Tracing their jumps on the paper sky
Where the fallen paper sleep.

Fallin',
We're always fallin'.
Callin',
"Hey come back, lost things!"

Ahhh, oh my God!
Ahhh, oh my God!

Summer was once where
the widest winter breeze.
I know it's somewhere,
hidden right behind our teeth.

Come and,
Come and call it.
Caught it
And then we lost it.

The song has a COOL stop-motion music video. Unfortunately I can't post links yet since I'm new, but you can search 'Lost Things' on Youtube and it should be the first video.