Finally hit the worst bug I have ever encountered and it's stopping me from playing the game outright.
The game loads fine and apart from the usual graphics glitches I cannot progress any further.

I've just completed the quest where you go with Farkas, from Jorrvaskr in Whiterun, to retrieve the broken blade fragment. I've been through the following ceremony, been given another mission, but am unable to play any further because I'm being hounded by Aela The Huntress and Skjor who keep initiating conversation thus stopping me from going anywhere. I have left Whiterun and they have followed. I am also unable to fast travel because I get told "You cannot fast travel while guards are persuing".

Is there a fix or have I wasted 3 months of hard slog?