A few thoughts. The first is that you're dealing with insomnia which is going to make a lot of things difficult that wouldn't be as bad otherwise. Are you more alert when you drive because of the big cup of joe you picked up on the way?

The second thing is that I think your premise may be flawed. I doubt that there are many car free or car light people who live in areas where there aren't alternatives to riding such as public transportation or even walking.

Finally, it's about mindset. If you've decided to go car free, you've considered (hopefully) how you'd deal with things like illness, fatigue and inclement weather. You're either in a situation where you've got some flexibility about when you get to work, you've got another way to get to work, and/or you're just going to ride come hell or high water.

For me it's a little of all three. It's extremely rare for me to decide not to ride due to weather. I have stayed at work a little late to avoid riding into the teeth of a bad storm. If I've worked really late one night, depending on what's going on the next day I might be able to come in later. I can always take a bus if I want or more likely, just cut my ride short by riding to the train station.

We had a lot more snow than normal this year. There were a few days where my usual route was either impassable or nearly so. I didn't drive on any of those days. I either walked to the train station (about a mile) or rode there. My office is another mile from the closest station so I'd have to walk another mile when the train ride was over.