I followed the link too. There's no way you can feel safe and work through your PTSD and these sexual issues with your brother in the same house! You really need to get out of there and if not, stay with your friends as much as possible. I totally understand what you are saying about dissociating during sex. I did the same thing all the time. I've never really been able to "ground" and completely enjoy it. I feel the same way about being with a man. My husband is in jail right now and I hope when he gets back, I won't be having the same feelings about sex, but I know it's gonna take some time & i should talk to a therapist about it. About pelvic exams, you're gonna have to deal with it. My doctor always told me to wiggle my toes to get through it. I dissociated during that too. These are really things you should try to talk to your therapist about. She could probably help you a lot more. Try relaxation exercises, yoga, self-hypnosis, etc. You won't feel like this forever, one day you'll feel better.