Need help!!

I was sexually assaulted by a step sibling once 7 years ago (16 years old)  and then again 5 years ago( 18 years old). I felt really ashamed and guilty and never said anything because my father would have just brushed it off as me trying to break up him and his new wife. I have not seen the step sibling since five years ago. The only person who knows about it is my husband. I had a nightmare about it last night and it has me pretty shook up today. Who should I talk to? Where can I go for help? What will happen if I talk about it? Anyone? Please help :( also 10 weeks prego with my husbands child and i feel it's make the emotions worse.