Well, money is a big one! Not just money, but what it represents -- security, opportunity, the ability to travel and to have wonderful experiences like horseback riding or live theater, the ability to see family who live out of state.
But also, I am out in a wider world, I have friends at work, my daughter gets to hear about what I do and things I learned at work. She has a model that there are many things she could do in her life, and she loves visiting my office. My adult life does not revolve solely around her, which I think would have been harder for me to avoid if I were home -- she's an only child, she's too much the center of the household as it is!
I'm prone to depression, and I think staying home, with no external structure to my days, would have been disastrous for me. I get up, get dressed, and go Do Things all week, and then get to thoroughly enjoy my daughter when home. I get to use my hard-won professional skills and do something that I'm pretty good at!
Also, my husband gets to be a fully involved father. In fact, he lost his job two years ago and only recently found another (so the "security" issue of me having a job is something I take VERY seriously, because if I were a SAHM we would have been in pretty dire straits), and during that time he did school pick-up and spent much of the summer with her. We've never had the dyanamic that I sometimes seem mentioned by women who are home full-time, where there's "us = me and the kids" and then there's "the guy who pays for everything but isn't part of US because he's not around that much."
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