Well I didn't read the whole thread, but here's my situation:

I just got back into cycling in May of last year, when my kid was already 2 1/2 years old. My wife stays at home, and the kid can be a handful for her at times. With a bike commute route of 14+ miles each way (using the route I have chosen as the best, though not actually having done it), the commute would take probably 1h 20m each way at least, where driving takes a mere 20 minutes. That's nearly 3 hours on the bike in a day, 2 of which could be at home helping around the house. Plus I have to be at home AT 5 pm 2 days a week since my wife teaches Zumba classes in the evening on those days.

I only get to see my kid a few hours in the evening each day. 1h 20m of hilly, arduous, 2-lane no-shoulder commuting vs. 20m of driving - I'll take the driving so I can spend that extra hour with my son. I hope one day our work and/or living situation will permit bike commuting, but as of now it's really just not in the cards.

As for general cycling in itself, I can't just jump outside for a ride whenever I want, like I could if we didn't have a child. Because my wife stays at home with our son 9-10 hours a day, every week day, I feel compelled to help out whenever I can. If he's staying with the grandparents or something then I can ride, but otherwise for something like a night group ride I feel bad if it's more than once a month or so, since my wife then has to stay at home alone with our son during that time as well.