I don't know if the woman looked, looked adequately, looked and didn't see, or what. However, would not surprise me that a driver should try to left-pass a cyclist making what we might think of as an obvious "vehicular" left turn. Based on my experience, some folks have trouble conceiving of cyclists as doing anything but standing virtually still and have no "theory of mind" about them at all. A common and less deadly corollary is the idiot who tries to get around you 30' from a stop sign and ends up stopped next to you and half way in the other lane.