And some people make themselves into martyrs for their children, and their kids then have to cope with the fallout from this. As the daughter of a depressed and unfulfilled SAHM who gave up a great career for her kids, I feel that my teenage years would have been much happier if she had worked. It still affects our relationship even now, and I wish that my mum had recognised then what she realises now - that thinking about her own happiness would have increased the happiness of the whole family.
I am not jealous or guilty. Why would I be? I have my own career and I am financially secure. My dd sees her mum leading her own life as well as having a family. We can afford for dd to have all of the opportunities that we want her to have. She eats healthy, home-cooked food. She is very close to both me and her dad, and has a close relationship with grandparents too. Her teacher last year described her as having "exceptional emotional intelligence" and she is at the top of her class academically. She is a happy, healthy and much-loved little girl, and I fail to see how her life would be any better if I quit my job and stayed at home. 
I don't feel the need to criticise SAHMs for their choices and I have no axe to grind. I am perfectly happy with my own choices. But yes, of course I am irritated by the smug sense of superiority expressed by some SAHMs who try to assert that their way is the best way. Yes, you may suggest that I am guilty or jealous. I might equally suggest that your comments stem from a sense of inadequacy or a feeling of being unfulfilled - but my saying this doesn't make it so.
Personally, I do not think we should underestimate the importance of mothers making the right choices for themselves, whether that is staying at home or going out to work. An unhappy mother will not be good for her kids.