No, it is absolutely not okay to fear anyone that way. Your abuser was wrong for abusing you, and you are simply defending yourself in your fear, but what must be done is that you have to confront and accept what happened to you so that you can move on and live a happy life.
It was a terrible thing that was done to you, but if you hold on to that fear, it will follow you for as long as you let it.
I recommend that you talk to someone about your abuser and your abuser. Talk through your past in full disclosure; talk about your fears, what you thought at the time, your confusion, your anger, everything. You need to go back and fully process what happened to you. Some part of your mind is holding on to that fear, and in order to let it go, you have to work through the source of the fear; your memories of that awful relationship.
Also, visit www.newhopeforwomen.org for vital information on recognizing, surviving, escaping and ultimately preventing abusive relationships.
If you would like to discuss this further, my inbox is always open.