I'm a Cappy with a Pisces moon and Scorpio stellium which included both Mars and Venus in Scorpio. What you said below describes me to a "T"....
"I attacked because I felt violated....heart was crushed, but you wouldn’t have been able to tell that. I was so cold.....Poker face....SO said that I didn’t even seem to have any emotion."
I can look at and THROUGH that person who hurt me in the same glance and make it obvious by my presence alone that I am removed from them. I have been told by various people on the receiving end of my cold shoulder that there is nothing colder.
I have attributed this to Scorpio. And as not just a deserving consequence, but really, as a self-protective mechanism. Scorpio for me has been a double edged sword, one side magnifies intensity, depth and passion, the flip side of that being pain is much deeper and more profound. So I have to remove myself to some extent to deal with it.
I not only shut that person out, but I retreat within to restore myself and possibly to establish healthier boundaries so I am not hurt again. Self-preservation I feel is the inner motive. Atleast for me.