Do you believe you have the power to change what you dream about? If so, how do you control it?

My boyfriend and I have a rocky past. We sat down last summer and agreed that we loved each other and wanted to go in a different direction than we had been going – one that ensured strength in our relationship rather than constant fighting and hurt.
In the months since, our relationship has been so awesome – more wonderful than I ever could have hoped! The problem is, I have had so many bad experiences that my subconscious is rejecting this. Every morning I wake from a dream that involves some sort of horror between us – a drunken brawl, a betrayal, or most recently, a new wife who was sitting in our apartment when I arrived home.
In the last dream, when he told me that he was married, he also slammed the door to our apartment in my face with a resounding “BYE!”
I have talked through these dreams with him, and he is always very reassuring – “I will never ask you to leave. I will never kick you out. You’re my best friend, sometimes my only friend. No matter what happens between us that will never happen.” These are the sorts of things he whispers to me, trying to break my subconscious anxiety. And it isn’t just words – he is very open about everything with me. He does special things for me, even things I know he hates, he just does them because he knows I enjoy them.

I want to be fully committed to this, but these dreams I’m having stick in my head and make me feel like getting screwed over is somewhere just around the corner. My boyfriend is being so awesome about trying to help me overcome it, but I know it’s nothing he is doing that is causing this – its something in my head. HOW CAN I BREAK MYSELF OF THIS?? Once my day gets rolling, I have no issues with it, the dreams are out of my head and I’m happy. In the mornings, though, after those dreams, I’m a wreck. I really want it to end. Please help!