It would have been great if the left-turning bike would have waited for you to get through the intersection. That would have been the ultimate courtesy, anticipating that cagers might follow him through and possibly wreak havoc on you.
If you make no contact with another vehicle, to the police or anyone else that might be interested, it sucks a$$, but it just appears that you failed to control your vehicle during an attempt to stop. We all know cagers do the dumbest sh*t imaginable. Come to expect it ALWAYS.
Glad to hear you aren't injured...+1 for gear... -.5 for not having riding pants or some leg armor.
Ride Safe