No matter what you do about reporting B, please, please, please, make it very clear to him that you want nothing more to do with him. And then stick to it.
This broken wrist should make it very clear that B wants nothing good for you. Next time it could be worse. Get him out of your life before its too late.
"But now old friends are acting strange,
they shake their heads, they say I've changed.
Something's lost but something's gained in living every day
....it's life's illusions I recall, I really don't know life at all. "Joni Mitchell