When my mum left my dad (um thirty-something years ago) she set up house with another single mum. It seemed to work well for them, half the rest cost, much bigger/nicer house than either could've afforded, and the benefit of another adult present/sharing babysitting, etc.

However you'd want to get to know the person a bit before you went for this, I would imagine that different expectations about tidiness, parenting styles, food use etc would all affect the experience.
Good luck, I hope you can find a really good arrangement that works for you!