First of all, you are NOT very stupid. Please do not listen to that old JW tape playing again and again in your head. That tape is there to keep you quiet and submissive. You can stop it, but it takes effort and time. Tell yourself what you already know: they are the liars, they are the evil ones, not you.
I'm so sorry, please know how many people in this life hurt for you, grieve for you and are with you, even without fully knowing.
Like you, I too sent letters and all it did was land me in hot water. That CO I mentioned? He sat in my living room and told me if I didn't "shut up" he would see to it personally that I was disfellowshipped. Why? Because I pissed him off. Not from being obnoxious but by relating to him what that MS had done to me as a child. He, like your elders, felt no pity, no love, his heart did not hurt. No. He felt anger. That said a lot to me back then, before the Internet and I thought I was the only one!
So I left, and my wife stayed in. Very awkward, but things turned out okay 13 years later. But I don't want you to feel what I felt for years, I don't want you to beat yourself up, or blame yourself or doubt.
As I said in my first post, Jehovah's Witnesses really really really want this issue to go away. This is why elders, not all but most, behave the way they do. You know there is no love in that organization, there is only guilt and pressure and no matter what you do it is never enough. Child abuse gets in the way of selling magazines, making meetings, studying and those beloved monthly statistics of theirs. In other words, people, even very innocent, defenseless people, only get in the way of numbers; how many magazines, how many hours, how many comments, how many meetings, etc etc etc.
If you look at the Witnesses that way, how they view things like oral sex and child abuse, makes a great deal of sense. Warped and cruel, but understandable. There is no reform, there is no way to make sense of it, the only option is to leave. Just like the faithful Christians left Jerusalem as the Romans fled, just as Lot fled Sodom, so you must flee.
Their view on child abuse is evil. Their treatment of children who have been brutalized is evil. Can a God of love, one who said it would be better for one who hurt a child to have a millstone tied around his neck and thrown into the sea, can that person exist where there is such evil? Not wrong-headedness, not misguided, but evil. Not one faithful Biblical character, no matter how misguided, ever would have treated a child in the way Jehovah's Witnesses do.
Look at what they do, and it speaks so loudly you cannot hear what they say.
It does get better. Please believe me.
Be well,
Chris