You can be heartbroken and also resigned that you are raising/have raised a dangerous person.
As a mother, you have all the same love and feeling for the angry one and you wonder what you did differently. You blame yourself until their behavior becomes so bad you begin to think of mental illness. Then you find out there is no cure. When I was raising children in the 70's and 80's they didn't give kids pills and I never heard of a mentally ill child - just retarded.
Certainly parents never looked for signs of sociopathy or autism or ADHD. The diseases were around but they just didn't have the names. I took my son to MANY psychiatrists and doctors - the best in the field and the consensus of all their advice - get ready for it - was "You have a difficult violent child. Be sure to give him lots of attention and my favorite, "Try to be a good listener--and if you can, remarry."
If you have ever seen "The Bad Seed" imagine being that girl's mother. My heart goes out to her mother. She probably didn't have the money or time to give her daughter the extra care and supervision she needed. I did and, hate to say it, but it didn't really matter. One psychiatrist saw my despair and said, "Hey, don't feel so bad-- if it weren't for you and all you've done, he would have been institutionalized before he was ten."