I had this at about the same time. My H would wake me, because I would wake him from my thrashing or crying. It wasn't always the same thing I was dreaming but always about him leaving me.
So I took some time to really really think about this, and where we were at that point in our R. What I found was I had a real fear of things that were outside of my control. I feared that he would walk in one day even though things were great, and say I'm done. I feared that he would cheat again, even after he did all the hard work to figure out why, and change those things at a very basic level.
I feared that my kids would grow up with a hatred for their dad if he left, and then it would spiral....
What stopped it?
A few things, one finally accepting that no matter what I did, I could not control him, and believe me that is some scary shit. He would ultimately make his own choices, no matter what. I could not force him to stay, he would stay because he wanted to. We talked about this at length, and he always reassured me, and once real R started he always told me his job as H, and dad was to make sure we were happy every day. He was consistent with that.
Lastly I think they finally stopped when I knew that NO MATTER what happened I would be ok. I was happy with me. I could make it without him, and be just fine. Spiritualy, financially, and fundementally. I was a pretty neat chick, and he was damn lucky to have me.
I dont' know if this helps you figure out how to wade through it. The other thing I did was start taking my Ativan at bedtime again for a while, at least if I was having the bad dreams I wasn't aaware of it.