What are people's reactions when you say you are a SAHM??
I haven't read all the replies (sorry for repeating what has already been said)
My personal experience - my Mum's goal in life was to be a SAHM. She gave up work for 'house duties' well before I was born.
My StepMum worked and her girls wished she was there for school functions etc and now they prefer to be a SAHM for their children.
I think in this day and age having both parents working is the 'norm' and almost essential to keep afloat. I would suggest the reactions you're having is perhaps jealously (for lack of a better word) they can't have the pleasure of staying at home with their children and be financially secure.
And they do say having a family is harder than any paid employment.