You are not alone. I have flashbacks and nightmares of my experience with a second marraige. I was deceived and cleaned out financially. She left me twice without saying a word, created incredible drama and problems for my kids. I went a long time without having the nightmares, I think because I was in a warm, nutruing relationship. However, I made some pretty huge mistakes and lost this relationship. With the added time alone, especially sleeping alone, I am having these nightmares every single night.
I think the solution is to get your life in order and feel safe and comfortable. I know when I felt that way my nightmares stopped.