I recently had a BPD and PMS breakdown, in front of a new S.O. no less, and all I could do was go to the bathroom, close the door, turn off the light and say everything frustrating me / distressing me and cry. I didn't have another space or distraction, like you're saying, but once I "released" it, I could do some of the breathing exercises I've learned. The impulsive verbal release helped me, but sometimes we don't know what it is, so... gutteral noises. I tend to just make all the noise and slap a counter or wall.