Hi Tuf, what a heartbreaking episode for you. No wonder your stomach is churning; I'm sure that would be the case whether you were right or wrong. When an adult gets physical and shoves hard enough to cause injury, or slaps and bites a 10yo girl, it becomes a very serious danger to your family, and you have no choice but to remove him from your home.
I have an (adult) nephew who became violent under the influence of drugs and had to be removed from the home. He later said it was the best thing that ever happened to him, and that he'd had it too easy. He's not over all his problems, but he's getting there.