Normal
"when do you stop feeling sorry? when do you stop allowing what happened in his past to affect how he treats people in the present???"When you realize that your life and your family's life has suffered enough---at 15 he is old enough to know that life treated him badly, but that it wasn't you or your family who caused this treatment. His choices are his choices. There will come a time unless he changes his actions when you can' get him out of the trouble he causes. You would much rather have that happen now and not when he turns 17 and is legally an adult.
"when do you stop feeling sorry? when do you stop allowing what happened in his past to affect how he treats people in the present???"
When you realize that your life and your family's life has suffered enough---at 15 he is old enough to know that life treated him badly, but that it wasn't you or your family who caused this treatment. His choices are his choices. There will come a time unless he changes his actions when you can' get him out of the trouble he causes. You would much rather have that happen now and not when he turns 17 and is legally an adult.