Say that I was to set off half an hour of every day for doodling and another half hour for studying the fundamentals.

How long would it take before I could take a one-day pause and not immediately be knocked back to zero?

I like drawing and I have plenty of things I want to draw, none of them porn, but I have a handful of issues and one of them is not being able to see the light at the end of the tunnel.

The idea of missing one day and wasting four months of practice, or the idea of four months of practice not doing anything, scares me shitless.
I know there's no absolutes when it comes to drawing, sure, but I'd like to at least hear people's opinions about how many months/years it takes before drawing usually becomes "internalized".

Once you learn to ride a bike you don't just forget it, but what scares me about really putting in effort is the idea that drawing ability needs to be maintained every day without fail or you're back to symbol drawing or even stick figures because you missed a day three years in.

I have a whiteboard in my hallway and drawing supplies at hand, so I'm confronted with my doodles dozens of times a day and always have the opportunity, but I really don't need one more thing to be obsessive about.

If I knew that every drawing got me further, I'd be overjoyed, but the idea of never being able to spend a day away from my place without dropping it all on the floor is really hamstringing me.