ExP and I used to be engaged and lived together. Then we had a baby and it all went wrong, lots of arguments, we had a second baby but by then the relationship was awful - no love, just arguments and we split up, he went back to living in his house and we sold our joint house.
I bought a very small house near him and was much happier as a single parent, the dc were able to see lots of their dad, I was self sufficient as working and good childcare. Then I was made redundant and so became sahm and we spent a lot more time at his house (more space, big garden etc).
So now ExP has asked us all to move in and says I could let out my house. On one hand it's appealing - the dc have both parents, lots of space, I get more help with dc. On the other hand we wouldn't be married and so if it didn't work I'd have to leave but I wouldn't have a home. I'm under no illusions it's not a great romance, he doesn't like spending much time with me, we never have sex and he's not bothered about sharing a bedroom (we'd have separate ones).
However I feel bad if I turn his offer down as it means dc don't have the chance of a single home.