Hi HPDhelp:
Your reaction is human, don't beat yourself up about it. NC is the ideal because getting frustrated with them gets us no where and makes them the centre of attention, their life objective...

! That said you have a right to "FEEL" and a right to "REACT" in consequence according to those feelings; regardless of her desire to be the centre of attention. If that means breaking the NC rule then fair enough.
Know that my written exchanges with my X were so explosive (from my side; she always kept frigtheningly cool!) that I stopped all contact because my thoughts and feelings were completely ambivalent and unstructured! Felt tenderness on the one side and abhorrence on the other, which led to numerous "hot tempered" and sometimes "bitter" emails. Then I forced myself to NC, but had to live with 3 years of intestinal spasms instead because I was keeping it all in side.
At the beginning of this year (therefore 4 years after it all ended), I determined that I wanted to play a game on her (my little devil was ready to play with hers, and I had no scruples given her many games based uniquely on her rules that i endured; usually unkowingly at the time...

!). I opened an annonymous email account and wrote down much of what I had learned about HPD, and how I found her treatment towards others (I say others, because we are numerous to have suffered the same treatment from her...) despicable. Ten days later I wrote her a nice letter from my regular email account, just to make sure that she was still using the same one. She did reply to that in a very superior, aloof and ultra-romantisised way. It was then that i decided to put our specific case on the table, as I knew she would get the mail and read it. I had learned enough about HPD, about myself (good and bad...), and about specific events to go coldly point by point through what happened and challenge her for a explanation or admittance that she did deliberately try to break me, in which case I welcomed a "SINCERE" appology from her side. Of course, caught with her knickers round her ankles, she did not reply. but I know she received the mail, and therefore I know she knows that I eventually rumbled her (according to the little I found out or already knew, the other guys have cowered away into corners after her treatment, and some remain her puppets...). Let me say that since that letter i feel a million times better, and all my intestinal problems have solved themselves...

! .
By chance, I since met her best friend from July 2006 through July 2009. She spoke to me a great deal about my X. I learned that she too told my X where to get off because the relationship had become unhealthy, she described my X as "strange", "needy", "disloyal" and "superior" (her words not mine). I learned through that conversation that my X made her decision to take the job in Boston because her various acts of back stabbing resulted in her loosing support from most of her colllegues here; and stupidly, her not understanding why (I am again struck here by the HPD's lack of empathy with others and their feelings)...

!
All that to say, that the NC rule can be very useful, and highly recommended most of the time, but its whats best for you and helps you make the next steps forward that is important. If that means breaking the no contact rule and blasting off at her; thats fine.
Good luck, Musician