I've been to therapy myself, I was so afraid of having my trust violated that I didn't go through it that much.
I will say that you brought this on yourself. You should never tell them you're thinking about killing people, I'm not f*cking around or trying to be a tough guy behind a computer screen, either, I'm speaking straight. They asked me if I had thoughts of that nature and I lied, if I hadn't, they would have had to do something about it. Either have me committed or tell my family or dope me up, you should NEVER tell them about those thoughts, people just don't understand.
Point is, you can't trust them. Therapists don't want you to be happy, they want you to be 'normal' - either through accepting all the sh*t that's unfairly put on your plate or drugging you until you become a f*cking zombie and don't even know your own name. I honestly think people like us need to stay the way we are, sick but independent. After a while, it kind of becomes part of you, and the thought of getting 'better' feels like your family wants to replace you with someone else.