The taxi driver probably did the best he could, we really don't know what Libby said to him. What we do know is that he came forward and has helped the police, he also helped Libby when she fell over, so this shows that he did take some care to ensure that she was 'safe' before he left. Libby was already headed away from her front door at the point of falling over... "Walking away from her front door" suggests she walked to her front door, realised she didn't have her keys and then walked away. The taxi driver may have been waiting at the side of the road to see that she safely entered her house, because he was still there to offer assistance when she walked away and fell over. For all we know, Libby may have told him that she didn't need his help. We know that grey beard offered to help and then got back into his vehicle, suggesting she declined. I'm sure they all wish they had done things differently, the doormen, her friends, the witnesses, the taxi driver - but nobody could have known, and I'm sure everybody did what they thought was best at the time. I have been away from this page for a few days, very sad to see that there isn't any new information. I was walking outside last night, it wasn't below freezing and I had a coat on, but I felt cold and miserable walking through the wind and rain. I just couldn't help but think about the freezing conditions that Libby would have been in that night and how she would have felt. It's just so sad, I think about her all the time.