In my experience, there are periods of time in which they ease up or off for a little while. I have yet to witness them disappear from my life entirely. Just an hour ago I had a bad flashback and I'm glad no one's around to see or hear it. I've seen some people who haven't had a flashback or anything in years and then it just happens one day. Trauma is a hard thing to shrug off. It will take time but maybe you could go through a very long grace period without them, hell maybe even be cured of them; but it takes a lot of work and self awareness to get there.