The reason we "go back" is not to retraumatize ourselves and relive the pain, but to get in touch with the feelings that abuse gave us. That's important because those feelings continue to affect us, even though we may not see that so clearly.
Once we see that we're not gaining anything new from the past, then it's time to leave it behind and devote our attention and energy to where we are now, in the present. We use what we have learned from the past to look at those old feelings, learn how they have misled us, and discover ways to keep that from happening again. It does take time, but that's what we ultimately gain - an ability to live with the past while denying it any further power to hurt us.
So yes, I imagine you will always remember what your brother did to you, just like someone who has been in a bad auto crash will always remember that. But that past will not "own" you anymore. It will not be able to hurt you and you won't fear it. You will be able to recognize your own worth, plan a future for yourself that's rewarding and fulfilling, and move on to realize your own amazing potential - not just as a scientist, Lewis, but as a man too.
Nobody living can ever stop me
As I go walking my freedom highway.
Nobody living can make me turn back:
This land was made for you and me. (Woody Guthrie)