Sorry, you miss the point.   It may sometimes be hard to tell when a threat should be reported.  This is not one of those times; this man made repeated, specific statements of intent to kill specific people, and his friends just looked the other way.  The anonymous hotline is meant to give people a way to report threats without stigma.  Doesn't matter what the girlfriend did to him.  Surely you don't justify his actions because she disrespected him.