if you think things are gonna go tits up just dont bother moving her and the kids in at all if i was single staying by myself and i met a bird with 2 kids it wouldnt bother me about the 2 kids bit i would help them out to get a place etc then take it from there i wouldnt go rushing in to move this bird in especially if your house is at risk and at the end of the day lots of people have brief relationships where you think you love the person etc and when you really get to know them they arent the person you first thought but by then shes up the duff moved in met the parents etc and thats when the fireworks start and jeremy kyle gets a bell.
some people have regrets in their relationships make sure you dont have any about yours cos it could cost you in the long run.