I was originally planning to walk the Frances route in July 2019 and have booked airfare and taken time off. Now I am reading about the Primitvo route and trying to decide between the two. I have a fear that one may be too crowded but the alternate fear is that the other may not be as safe for a solo woman who is winging it....
Hey Ponygirl,
I did CdN "alone" in July/August 2017 and am headed back to Spain to do the Meseta in just 2 weeks. France to Finisterre took me a very chilled 35 days. Safety is unlikely to be an issue, regardless of which route you do. I would suggest thinking more about fitness, and how long/far you want to walk. Also, you'll only walk alone if you want to - making friends/family on the Camino takes no time at all if you're open to it, and these people could become a permanent part of your life. I still have contact with many of the people I walked with and travel to meet up with some of them every 2-3 months. It's up to you how solo you want to walk.
You have 5 weeks, which is a wonderful amount of time!

The Primitivo is a lot like the Basque country on the CdN - which means it is a lot of up and down, and the the weather might be unpredictable. That being said, it is said to be
beautiful and you will bond with the people even more because you're in the struggle together and the stages are pretty standard (unlike the CF). I'm assuming you're wanting to walk for most of those 5 weeks; if you're willing to walk a few weeks before the Primitivo - from Bilbao or San Sebastian for example - in order to build up your fitness, the Primitivo should be no issue. That being said, the CF will be fuller, which means both safer (numbers and all that...) and well... fuller.
At the end of the day, I'd say consider the information, and then go with your gut. Buen Camino.