Self sabotage in relationships

I'm trying to understand more about the varying levels of BPD and how it's manifests in everyday life. I've been reading that there has been requests in the medical profession that they create more of a spectrum of bpd and I agree that's a good idea. I believe I have bpd but have sort of been self treating with tips I have come across here for the past couple of years. However, I think my ex is a definite candidate for bpd as well. I know that a main component is fear of abandonment and unstable relationships. But I was wondering if any one here has cheated or set out hurt their FP or SO purposefully during episodes. I'm really trying to understand this rational so I can find closure for myself.

Basically what I'm asking is, at your worst and most triggered, how far can you go to be willing to push someone away so they can't leave and hurt you first?