Hi there, I have suffered with Major Depressive Episodes in the past but never been diagnosed with PTSD. Welcome to RYL by the way :)
I think it's good that you have been referred for EMDR, I've heard good things about that. You are right, it is to do with eye movements and memories and such.
I also think it's positive that you are going to be assessed by a psychiatrist.
Feel free to message me if you'd like a chat about anything.

xx