I do something similar except I’ll stop using my GPS if I’ve driven the route multiple times.

Do you use a calculator?

I've actually taken note of my navigational skills over the last couple years... I grew up in one state, and then a few years after graduating college, moved to a different state. When I was growing up, phone navigation didn't really exist as it does now, cars didn't have built-in navigation, and standalone navigation devices were slow and not all that great (at least the ones I could afford).

I find that when I return home, even 10 years later, I am able to navigate all the places I used to go unaided with ease, back-roads, niche routes, able to travel for hours without getting "lost".

When I moved, though, I had very recently gotten my first smartphone, and google maps was very convenient to "learn" the new area. I ended up just continuing to use navigation since it was convenient. I've found that beyond the major main routes, I don't have the same kind of "built-in" navigational skill that I do for my original home-turf. I never really learned the area.

I am moving towards a smart-phone-less life, and I've been able to let go of a lot, but GPS navigation remains a sticking point. I need to start training myself to navigate unaided in my current area.

I use them to find a new route. I'll try and drive back on memory. After that I should be able to find it on my own

Your brain doesn't have real time traffic information.