How many kids there are doesn't matter that much. As soon as there is one kid, divorce becomes a much more complicated issue. And if they caught you getting married and divorcing all the time, they might very well take away your children because you're "unstable".
I think unless the husband caused the wife to be unable to work, he doesn't owe her money. He does need to help provide for any children he has, because they can't work, but any adult can work, and if they can they might receive welfare. I don't think you need to be responsible for people you have been with after the breakup, they're adults and can find a job, not necessarily a good one, but they need to take their own responsibilities.
I believe it should be the same regardless of the genders involved.
Certainly, helping an ex out until they find a job is a nice gesture (be it financially or by letting them stay in your place, or whatever) but I don't think it's something that should be required between two grown independent adults.