First: Wow! Thanks for being so open about the whole thing.
You really paint a vivid picture.
I know what supertom is trying to get at, but it's hard to do it with a mouth full of foot.
A lot of people wear the sexual victim as a badge, and become a victim to garner sympathy, etc etc. But you said quite strongly that you aren't that kind of person, you aren't interested in that. What you want is a path to travel in order to free yourself from the subconscious mess it created in you when you were young.
There are several ways this can be done, I've heard of people using NeuroLinguistic Programming, I've never tried it, but it's worth looking into. There's also a course called the Landmark Forum run by Landmark Education which is about freeing yourself from the hidden patterns that run your life to get your power and freedom back. At about $500, it's out of reach of some people, but definately worth it. Therapy could also help, but in my opinion, it costs way more, and doesn't help anywhere near as much.
If you don't like those, you can try self discovery. The success depends on how willing and commited you are, as well as what research you do. It's slower and sometimes harder, but often way more effective.
You are already definately on that path, just looking at what happened and the ripples it has caused in your life will open up new options. As you go through your life, and not all the time because that would stress you out, you can be aware of subconscious reactions. As it happens, realise that you aren't choosing to do something, or feel a particular way, it's just an automatic reflex. Then see if it's caused by something that happened in your past related to this incident. 99% of your automatic reactions are caused by things in your past. In the moment that you see what you are doing is connected to what happened years ago, the link is temporarily broken, and you have another way to react. If you are about to hug a friend, and you feel uneasy, then realise the unease is from this experience in the past, then give up the unease and hug the person anyways. Just doing this weakens the link and brings back more of your power and freedom.
Examining your past is also a good idea. Don't lose yourself in it, and don't use it as a crutch though. It's been and done, and it's all over. What's important though is looking for the links that are still effecting you in the present, much like chains still dragging you back. Like with the incident with your cousins, what kind of automatic responses did you create from that? How about with your brother, where there any negative longterm repercussions.
I just realised that this is all on an intellectual level. It will definately help, but we should bring up the emotional and physical sides as well. And I just realised I have little to no experience in this area.
When you feel conflicting emotions, or even grouped emotions, like love with fear together, then there's often a source of collapse in your past. The perfect example is what happened when you were 5. In a time of great fear, panic and shame, you related physical intamacy with those emotions. As your first sexual experience it would be devestating, so you've lumped them together. Then any moment you experience intamacy, the fear and shame are right there, and you freak out.
The challenge here is to cleanse your emotions, so you can experience them without the collapse. Discovering the source memory is a great start, explore it and see whether you want to keep it. Imagine yourself in a current situation relating to the trigger, such as hugging a potential boyfriend, and feel what arises. Is this real fear and shame? Are the emotions real, or are they an echo? Feel them, accept them, and dismiss them. Just let them come up, and fade away, while still holding onto the triggering situation. Can you work through the emotions to reach your power and freedom again?
Sorry about the long post. I hope you get something out of them. If not, I still have a whole bunch of other ideas and techniques.