Oh dear all this rubbish about "women have always had to and wanted to work"
No, the aim for most people historically has always been to reduce the time they had to work. Not just women. The fight for the eight hour day was all about reducing the working week for everyone. It was supposed to be only a start. Unfortunately, the struggle for a shorter working week appears to have stopped in its tracks about ooh, a century ago.
I swore I would never bother to counter any of Xenia's arguments again, but can't resist - the idea that it's a "risk" to be dependent on a man. Actually it's a "risk" to be dependent on an employer as well. Redundancy terms from a husband are generally better than those from an employer. Having a job/ career doesn't protect you from being dumped without money. Most people do not earn enough to cushion themselves against being dumped by their employers. Most of us are "a paycheque from poverty".
Yes I know, you're now going to tell us that that's why people who go in for low paid jobs where you are only a paycheque from poverty, like teaching, nursing, occupational therapy, admin, etc., are stupid and ought to only bother to do highly paid jobs. But that really is not a solution, if everyone wanted to be city bankers and no-one wanted to be nurses, the price of city bankers would go down and that of nurses would go up. As Gilbert and Sullivan so succintly put it "when everyone is somebody, then no-one's anybody".
In answer to the op, of course you're not unreasonable, you don't need a justification to be a SAHM. Bringing up children doesn't stop being socially useful activity because you have an emotional and biological investment in the children you bring up (no-one has ever explained to me properly why it's work when it's done by someone who is paid and worth at least £400 a week, but not work when it's done by a mother and worth nothing).