Sexual Abuse Support Group
Sexual abuse is a relative cultural term used to describe sexual relations and behavior between two or more parties which are considered criminally and/or morally offensive. Different types of sexual abuse involve: Non-consensual, forced physical sexual behavior such as rape, incest or sexual assault, or psychological forms of abuse, such as verbal sexual behavior or...

Have you tried writing your dreams down? It can sometimes be helpful and there’s also a process called image rehearsal therapy that can help by changing the ending to dreams then practicing them before you go to bed.
It’s okay if these methods don’t work right away. But if you keep trying different methods, you will likely find something that helps reduce those dreams. Hang in there, remember that you are (hopefully) in a safe place now and that family member can’t hurt you anymore.
((Hugs))