Be very aggressive!
I don't think he's currently stalking me or anything, but I do think he enjoys the reaction he gets.
That
is stalking.
I can't keep him from getting emergency medical attention ( but believe me none of his visits were life threatening).
You can report him to the police for stalking you in the ER. You can show them what he came in for. Those records can be subpoenaed if necessary under seal, visible only to the judge. There should be videotape available from security cameras. He can be required to go to another ER by the court. His parole officer can monitor him.
My co-workers are understanding and have covered for me when I have had to leave. They only know because I had to explain why I started panicking when he checked in.
Seriously, I suggest that you should read "The Gift of Fear".
PTSD is not synonymous with panic. Given the situation, your panic is entirely reasonable. PTSD is when you are
long removed from a dangerous situation and you can't calm down or stop feeling and acting like there is a threat there. PTSD is not having panic and flashback feelings when a threat from the past shows up again. It sounds to me like your unconscious is telling you to take care of this.
I did report him to the police shortly after the rapes and had a restraining order for awhile. I chose not to pursue any legal action.
Yes, women often do that. The most common reaction is to curl up and hide and hope it will disappear on its own. Sometimes it does, for a while. But that female pattern is exploited by rapists. They know that most women will react and feel powerless, and afraid. They know that most women are taught not to fight, are taught to be good girls. They want a victim and victims are easy to find. That fear they see is what makes them feel powerful. It gets them off.
Your observation that this guy is enjoying the reaction that he is getting is correct. He is. That reaction is what a rapist or sadist lives for. It gets their rocks off. So what you have to do to stop him from getting his rocks off is scare him. You need to make it clear that he isn't going to control you and that you are going to pursue him and get help for it until he leaves you alone. You need to make it clear that if he attacks you he's probably going to die. That stops his enjoyment of you as victim.
There is a big problem you have here. He is getting off on seeing you afraid. For a rapist that is the equivalent of seeing you do a strip tease. It's titillating. He is going home and fantasizing about it - guaranteed. (Yes, it was my business to understand predatory, sociopathic psychology. I know it far too well.)
So tell your supervisor. Tell your husband. And for god's sake make a formal report to security and call the police next time he shows up!
Look, if something happens to you, if suddenly you disappear, the police won't have any idea where to look, who to look for, or anything. (Women disappear and get raped all the time.) This guy, if he's been through the prison system knows this. He's spent years swapping stories with other cons about how to not get caught. So the next time he comes to the ER, call the police and make a report. Make sure the guy sees you talking to them and let the cops talk to him. Get angry. Don't get his rocks off more.
That way, at the very least, this guy knows that if anyone calls in about you the cops will already have you on file and will be able to move fast. This isn't a game. It's your life and sanity on the line here. Be aggressive. Use your fear of him to fight back. That's what fear is for. Fear can make you ferocious if you let it. Fear and fury are a hair's breadth apart. You have every right to fury.