I wonder if you don't have complex ptsd. I hear this a lot from the kids I worked with.

When your body is constantly telling you your in danger, it prevents you from forming attachments. Focusing only on survival. When your living in this state you have to find ways to expend the energy.
Hence the fights and the trouble.
This is more common than you think in kids who experience several traumatic events in a short amount of time where they have no control.

As the name suggests it's complicated and there is no quick fix, but it can be managed and over time you might even be able to be there for your boy.
But one thing at a time, first you need to trust someone enough to find help.

All the best,