I have BPD (31F) and I just scheduled an appointment to start DBT soon.
I like to trick myself into thinking I have it beat because I take my medication and overload my schedule to stay busy but I don't. 
Today, after almost a year, I lost it. Everything I bottle up came pouring out and I can't even remember what set it off. My partner said something to me that pissed me off and I began screaming as loud as I could, crying and punching myself. I was  having suicidal thoughts (I'm okay now) and I've been disassociated since it happened. I started reading and came across something that made me realize how toxic I've been for a while now. I'm not sure why I didn't resort to getting angry and blaming someone else like I'm prone to do but instead it hurt me to my core and I bawled at my behavior. I'm so disgusted with myself and I don't want to be like this anymore.