Hi, Katherine,
I have walked the Primitivo four times, and once was in October, years ago. Even then, there were others on the route and this was before it was anywhere near as popular as it is now. I always started out alone, and always met people to walk with if I wanted. The Primitivo is a very popular route now, but traffic will drop a lot at the end of October, I bet. The fact that the private albergue in Grandas said it was closing on Oct. 31 probably reflects that. I have walked many stages on the Primitivo alone and without seeing anyone else and never felt threatened or nervous. I actually relish the stages when I walk totally alone, but that comes after many years of walking caminos. But when people ask me about this, I always say that I would never recommend that someone walk alone who is feeling nervous or anxious because that’s a sure way to ruin your camino. The camino is extremely safe, but fear comes from emotions and not always from facts. My telling you that statistically I am safer walking alone on the Primitivo than walking through my town at night is not going to help you sort out your own sense of anxiety/nerves or lack thereof! But I can say that I know many women who have walked alone, on the Primitivo and on other much more remote routes and they wouldn’t have it any other way.
The Primitivo is very well marked, but having GPS tracks on your phone might make you less nervous.
You’ll make the right decision for you after careful consideration. Buen camino, Laurie