Dealing with PTSD symptoms

Last year I finally took the steps to leave my abusive boyfriend. We had lived together for 3 years and during that time I was assaulted and taken advantage of. Currently, he is serving time in jail for one of the many assaults against me. I have a restraining order against him and I moved into a new apartment so that he wouldn't know where I lived. I know that he will be released soon and that makes me nervous. Lately, I haven't been able to sleep much, maybe 2-3 hours a night. When I sleep I have nightmares of him. I continually switch from feeling angry to sad. I've tried coping techniques to deal with the anxiety but I still feel like I'm on guard.