There are alot of things going on here, but in reading your post, I have to tell you that you have to step back and ground YOURSELF. If you are losing sleep and not functioning very well you will be of little help to anyone, including him.
I can't say that I've ever had to deal with the degree of paranoia that you describe your boyfriend as experiencing. I would be surprised if there weren't drugs involved, and I wish I had some type of advice to give you with regards to this, but I don't know how close he will allow you to get to him if he thinks you want to kill him. I'm much more familiar with what mogigo mentioned, situations that have triggered my SO to be "set ups" when they actually were harmless situations, or situations that made him uncomfortable for whatever reason. In those types of situations, we've done just what mogigo had done, excused ourselves from the situation entirely. In life we all have to pick our battles, if something made me so uncomfortable to the point where I couldn't relax, I'd get the hell out of there too.
You can give him space and move forward with your life. He knows where you are if he needs you. You can text him, email him, leave a voice message just as a reminder that you are thinking about him and that you care about him, but you can't lose yourself in all of this.
I can imagine how much it must hurt to think that he feels you might kill him, but you have to realize and keep in mind that these are not rational thoughts he is having. You have to know that it's nothing you have done to make him feel this way.
You said he won't listen to you, so when you talk to him again, try listening to him. Try to find out "where" he is exactly. If it were me, I'd refrain from telling him what this is doing to you because if he's as paranoid as you say, this won't penetrate. I think you'll feel better if you listen to him and maybe gently raise some questions to him about any alcohol or drugs he may be using, or why he feels the way he does right now.
I don't know if I've been any help to you, but I really feel for you right now.