20 something year old tourist ladies are completely capable of driving themselves off the road without drink, drugs or any other drivers being involved. Picked one off the road myself a few years back, had got off the plane (CM) in the morning, rented a m/c in the afternoon and attempted to drive up to Wat Doi Suthep. Fell of at the first steep bend, sliding across the oncoming lane and into the drainage ditch. Lucky for her there were no oncoming cars or glass windows to drive into, but she wasn't wearing much and lost a lot of skin all over. I drove her back to her hotel, and my pillion passenger drove her m/c back.
Call me a sexist if you want, but I've never seen a guy do that!