Secret_Salope, It is a sad fact that both you and your half brother were victims but on different sides of the fence. Have you spoken to your sister about what was taking place, does she have the same flash backs? You have started the road to recovery by sharing your story with others that have had similar experiences, but now you have to go that short step further by seeing a therapist that deals in abuse in childhood. Before you go to see one, ask him over the phone if he has ever dealt with childhood abuse before, because looking through this thread I have noticed there are an awful amount of fools out there.
I would just like to say though that what took place between you and your husband was a trigger, and I know from experience that all the therapy in the world will never stop you receiving them, and as you go through life you will receive many more. I also fear that by going to see your half brother might just set off more and worse, it could even have a devastating effect on your now grown up life. There are certain times in people’s lives that going back to face your demons is the right way to go, but in your case I feel that it might do you more harm than good. The other thing is if as you say he is now married with children, he might just blatantly deny it ever happened at all, and it will be to protect him and his new life, and that might put your mind in a greater turmoil. I am not a therapist I am only pointing out the pitfalls of not seeking the best help you can get, I hope this has been some help in showing you the correct route to take.
This is not advice but just my thoughts.
Regards ian 2411