I think the first thing that you have to do is to learn to not care what other people think. Truly.
There is no "right" answer. The "career woman vs. motherhood" is also a false choice. There are a million shades of gray in the middle, that many people don't see. You don't see it because you aren't living it.
You are looking at this from the lens of a career woman, who is "letting the sisterhood down" by quitting. But that's not real.
My friend in DC joked once that "there are no SAHMs in DC except military wives". Yes, there is an element of truth to that (DC being a high-powered place), but he's a dude without kids. So he doesn't *See* it.
The thing that helps the sisterhood is to be you. Maybe you quit your job and never look back. Maybe you quit your job and realize that SAHM is not for you, and you miss the corporate gig. So you find another one that requires less travel. Maybe instead you start consulting. Maybe your old job calls you desperate for help, and you negotiate a 1/2 time or 1/3 time thing.
Any of those are possible, and they happen ALL THE TIME. I'm a mother of 2 (a bit older than you) and I work FT.
- My FT work is not 50 hours a week, it's barely 40
- I have a ton of flexibility to volunteer at the school, work at home when the kids are sick, leave early for baseball practice
- I cut my hours to part time for a few years when the kids were younger
I have friends who work part time. Or they consult. Or they started their own business. Or they teach one class a semester at the college. Or they are teachers and have summers off. It's very very common, and of course, I see it because I'm a mom with 2 kids who knows a lot of other moms.
So you just have to do YOU. What feels right when you are sleep deprived with a newborn is going to feel different when you have 2 kids in elementary school. What feels right when your kids aren't in any activities might need adjustment when they play traveling soccer.
The great thing about being frugal, or FI, is that you have choices that some people don't have. I really enjoyed my job and climbing the ladder ... until shortly after 40, when I got a new boss, and found that glass ceiling. It's pretty tough to do the soul searching involved with that. But I decided to roll with it - new boss, new amount of flexibility (and a second kid). I find that if I'm not being rewarded at work, I'd rather do more for my kids and get rewarded there. So I do!
I understand letting down the sisterhood. One reason why I was so adamant about working part time for those years is that I felt it was my DUTY to prove to the men in the tech sector that it can be done. That you can do JUST as quality work, at the same level of difficulty, for just fewer hours a week. If I don't do it, who will? Many women cannot work PT because nobody has done it before and proven that it WORKS. And sadly, you have to do it individually at each company before it becomes "normal".
A little backstory, I worked for a boss who would only let me go part time if he demoted me. So I stayed full time. He left. My new boss was fine with reduced hours at the same pay and job level. It was fantastic. I got a new boss who said "I don't believe in part time". "But it works". "I don't believe it works." "Let me prove it." "No." "I quit".
Went to a new company part time (ironically, my old boss). At that prior company, two of us were working part time (the only two to have babies there). About a year after I left, they had pressured her to work more hours SO MUCH that she quit to become a consultant. A couple of years after that, another friend of mine there had a baby. (It was a 30-person office, with a handful of women engineers, three of us in our 30s.) She asked to go part time. They let her, with a statement "maybe we didn't handle mm's situation very well". So yeah, they learned their lesson. But then they pressured her to go full time again after about a year. So she quit. Fast forward a few more years, now they have *another* young woman there, who is now a mom, and is working part time. And they are not putting undue pressure on her to go full time. So a recap: it took three women quitting before they realized that they were making a mistake. They are *very* slow to hire, so they lost a ton of productivity with each person leaving.
(The bonus of working part time to show it can be done is completely aside from the fact that part time work is the best of both worlds for me. I get to work and get the satisfaction from that, but I get the flexibility to be with my kids and take them to the park every day, etc. And exercise. And sleep.)
So yeah, as others have said, don't judge others. It doesn't make you more "right". You have no idea why they choose the path they choose, or what their options are, really.