Hang on....
The motorcyclist was behind her in the lane to her left, she had her signal on in plenty of time to make a lane change, and then the motorcyclist "flashed by" her as she started the lane change?
Why the bloody hell wouldn't the motorcyclist just let her change lanes, as she was indicating she intended to do, instead of trying to hog the lane and tear by her before she could make the manouver?
If that's really how it happened then that is some pretty stupid riding if you ask me. It's the 403 in heavy traffic - that is time for survival mode, not asserting one's claim on the lane, or the right to travel much faster than surrounding traffic.