I read it as the following from the facts in the text (my comments in parentheses):
Driver:
-> I decide to overtake two cyclists on a bend on the other side of the road (we don't know which direction the bend is)
-> I think it is safe because it is clear
-> At some point I see two cyclists in a line. I admit I should have seen them sooner, I don't know why I didn't
-> I decide that there's enough room to drive past at around 50mph (squeezing them into the side of the road coz they're bikes and don't take up any room and fuck 'em anyway)
-> One falls in front of me and I kill them (she does stop)
Cyclists
-> Lead cyclist and g/f see the car coming straight at them ( FUUUUUCK)
-> Lead cyclist - takes evasive action, slows down (and pulls to the side?)
-> Following cyclist clips the rear wheel (this is the really tough bit for the lead cyclist - apparently he slowed, suggests that his g/f didn't react the same way, I don't want to imagine what he must be feeling but it ISN'T HIS FUCKING FAULT)
-> Girl falls into path of car and is killed