I've been doing EMDR on and off for over a decade. I can honestly say it has literally saved my life.
The reality of it is, it can make you feel worse before you will feel better, but as time goes by and the more sessions you have, I promise you the more you will understand and you will be desensitized to your past traumas. I will also tell you that the process is not easy by any means, and you will have days when you will wonder if you are doing the right thing for yourself, BUT I can also promise you there will be days when you will feel nothing but peace of mind and relief that while your memories will never completely go away, they WILL become manageable and you will not be as sensitive to them in the sense that you will reprocess them so that when you think of those memories, they no longer have the painful, destructive power they once did. Also, the day will come when, for the most part, you will find yourself at peace with your past and have the tools you need to deal with the worst of them.
For me, there are times between EMDR sessions when all you can do is let yourself feel what you are feeling and accept that it is part of the process of healing. I can remember many a time when I would sit in the floor, hugging my precious German Shepherd, Izzy, in my arms, crying and wailing into her fur as she laid patiently beside me letting me lose myself in my pain and suffering, licking me as she tried to console me.
One thing that is part of the EMDR treatment, is to establish a 'safe place' for your inner child. In my case, I created a meadow surrounded by an ancient forest for mine where she is cared for and protected by a mother wolf. In addition to the wolf, the trees and plant life surrounding the meadow protect her by not allowing any of the hurtful things, whether they are words or the actions of other don't let any of them through to my child self so that she is protected and no longer has to worry about being safe. No matter what, nothing and no one will ever hurt her again.
I hope this is helpful. Best of luck to you!

WW