I was a stay-at-home mom for three years. I would never say they were the best years of my life. Well, OK. The first one was. After that, they became hard, frustrating, boring, and sometimes lonely, too. I loved my kids, but I felt like I never got a break from them.
Unlike a job where you go to work, being a mother means never being off. There is no 9 to 5. You are on duty from 6 a.m. one day to 6 a.m. the next with little to no break in between. So yeah. If a mom can afford it, hiring a nanny so she can run to a yoga class or get a manicure or, hell, just drink a cup of tea with no interruption is pretty nice, indeed.
So why would any mom get down on her for it? A heated discussion on CafeMom's boards raised this issue, and the amount of judgement that it brought out was kind of shocking. My guess? It's a lot of jealousy.