A lot of us acted out when we were kids because of the abuse. Don't beat yourself up over it. I don't know what it would like to still have those people in my life, maybe you can get to a point where you can explain to them why you did what you did (I'm not saying you should or shouldn't, that all depends on the specific situation and your current relationship with them). The fact is that you were you trying to work through things that you couldn't understand. As a result, you made some mistakes. That doesn't mean you were a bad kid, it means you were a human kid and you had bad things done to you.
As far as people "bragging," you don't know if they are outright lying or it they are re-imagining the situation to hide their own pain.
I can tell you are worried about how people will react. Most people here will understand. Some of us did very similar things. Out in the world, not everyone will understand. But you can't wait for everyone to know the truth. You know you aren't a danger, you know you were doing your best with an impossible situation. There is no reason to let the guilt way you down. You were a child. A child in pain.
This was brave of you to share.
Don't be weighted down by guilt.
"As long as the child within is not allowed to become aware of what happened to him or her, a part of his or her emotional life will remain frozen . . . all appeals to love, solidarity, and compassion will be useless."
-- Alice Miller