I have a wife and two small children. I have also successfully started a business using only "sweat capital" and know the stress it can put on a marriage. So I might qualify to give you some advice. I am also starting another company and willing to move to Cambridge.

I am fortunate to have a wife who is very supportive and sees the payoff of me staring a new venture. If I win, she wins. Also, I plan to move the wife and kids to Cambridge for the summer. They view it as an "extend vacation". Well, a vacation with no money, but at least it is new scenery (new playgrounds are always exciting for kids!).

I don't think the "don't do it" wisdom is always applicable. It wasn't in my case. As long as you make some time for your family and kids, and as long as they know the situation is pseudo-temporary, it can work.

Besides, being miserable at your current job is probably just as a negative on your wife and kids as a start up. It is hard to come home and be a good husband/father when you are bored/frustrated all day.