Incest Survivors Support Group
Incest refers to any sexual activity between closely related persons that is illegal or socially taboo. Consensual adult incest is very rare. Incest between adults and prepubescent or adolescent children is a form of child sexual abuse that has been shown to be one of the most extreme forms of childhood trauma. If you or a loved one is a survivor of incest, join the group...

I use a dream talisman when I am enduring nightmares. It only helps me deal. It does not prevent them. I have yet to find a way to deal with the feelings without letting myself experience them honestly first. The early going of the experience brings me horrid nightmares.
My own dream talisman is a rosary I wrap around my wrist as I sleep. For you it will be whatever physical object which means enough to you, personally, that it can help you stay focused on the physical realm for long enough to shake off the effects of the nightmare. I also keep a glass of water by my bed so I can wash the taste of fear out of my mouth before I attempt to go back to sleep.