Marcia, you’ve had an interesting life! Given the consistent thread of wanting to work with children who are in “trouble,” I think you would be able to explain your path to med school with sound reasoning. It certainly makes sense to me.
No one else can answer your questions in a definitive way, because everyone’s approach is different. So instead I’ll throw my story out there and see if it helps you. Obviously this is all anecdotal by definition, because it’s what I was able to do. But one of the great things about this board is that you share stories with a lot of different people and in the process you might hear something that fits your situation.
Money - I can’t say what level of indebtedness is “worth it,” because everyone’s risk tolerance is different. I ended med school at age 48, approximately $150,000 in debt. I consolidated my loans a year into residency and am now paying about $650 per month against my loan - on a thirty-year term! It makes me chuckle to myself that at the current rate, I’ll still be making student loan payments at age 78. On the other hand, the interest rate is around 3% and so there is very little incentive to me to actually work to pay off the loan. For right now I will just keep paying it at the current rate; at some point I may try to pay off more of it.
Children - when I started my post-bacc coursework at GMU, I packed my eldest child off to college, my middle child was in high school, and my youngest was in 6th grade. During my med school years, I only had one kid at home but there were certainly stresses in the long-distance situations with my college kids. There were lots of, um, interesting situations. My oldest child struggled with college and depression and required a lot of long-distance coaching before he graduated; his brother did fine in school academically, but did things like go to the ER and almost get kicked out of ROTC right before graduating (!); my youngest, a girl, was on a competitive skating team, travelled a lot, had the drama in her life that high school girls often encounter, and memorably got busted for underage drinking one night when I was on call on my OB rotation.
They’re all now high-functioning adults so something went right!
I had the unswerving support of my husband through everything, and I can’t stress enough how invaluable that was. He had his own issues - during my second year of med school he got laid off from his VERY high-paying job - all of a sudden our “cushion” disappeared. Then during my residency he was treated successfully for prostate cancer. But regardless of the challenges faced by either of us, we stuck together and made time for each other - and this was really key.
Geography - well, I know that most folks do admit to themselves that they’ll have to move, but I was the exception, and proud of it. Given the ages of my children, and my husband’s well-established career, I was, like you, unwilling to move. I knew this meant that I’d need a strong application and so I worked hard to produce excellent grades and above-average MCAT scores. I only applied to GWU and Georgetown, interviewed at both, was waitlisted at both, and eventually got in to GWU. The way I looked at it was, I had invested over 20 years in my family and my marriage at that point and I wasn’t willing to do anything that messed that up - so medicine was only going to be an option on my terms. I knew it was a high-risk strategy but I would still do it that way.
I also chose a residency “on my terms” because I still didn’t want to move out of my hometown. Once I knew that I wanted to specialize in family medicine, I did “audition rotations” at the two local residency programs with the intention of working hard, doing well, and making a good impression. I got my first choice program as a result. (If I’d been trying to get into a more competitive specialty, I would have had to be more willing to move, I suspect. I don’t exactly know how that would’ve worked, I’m glad I didn’t have to consider it.)
Finally, on the subject of shadowing and volunteering - I disagree that these are necessary. What IS necessary is that your application demonstrate: 1, you have an understanding of what the practice of medicine demands of you; and 2, an altruistic sense of service to your community. I suspect that you’ll be able to demonstrate these things in your application without doing the conventional “shadowing and volunteering in health care” gigs…
(At the time I applied to med school, I hadn’t worked in health care directly in almost 15 years. My volunteer experience was all community-related NOT health-care-related.)
Marcia, I was fortunate to have a “coach” during my pre-med and application period who kept reminding me that every step along the way was just that - ONE STEP. You can take an initial step, resolve to do very well, and continue to try and figure out what will be involved in the next step. His most memorable statement to me was, “You’re not joining the French Foreign Legion, for God’s sake.” 
So go ahead and try on these ideas you’re toying with - keep exploring - take one step, or two, or three - and just like driving on a really dark road at night, each bit forward illuminates a little more of the path ahead. Good luck!
Mary
I wouldn’t worry about that.
. Well-said, Mary!