I'm in a similar predicament. My dreams are not always or necessarily sexual but I dream more often of my ex husband than my husband. And the dreams are always that I actually want to be with my husband but it's the ex I get instead. These dreams are frequent even though I have not seen my ex husband in almost 15 years. I am always left feeling horrible about them. Almost as though I am being unfaithful to my husband whom I adore with my life and would never ever cheat on.
I wish my ex husband would leave my dreams alone. I hate the guilt I feel over something of which I have no control.