I once didn't have the choice, I left my abusive husband to live with a friend who owned a very large house. She had been left by her husband, with three small children, and I had my daughter. Yes, it took a while to adapt, but we had an amazing time as well as sad, broke and unhappy ones. As she said - you do need a hug sometimes. We gradually did her house up to accommodate other tenants over a couple of years, and saw many men and women passing through, although some stayed for years. It wasn't that they couldn't afford to live elsewhere - she had a couple of very big flats in that house, as well as just rooms - it was that they wanted to be able to have company when they needed it, until or if they felt able to face living alone. If anything happened to DBH I would go back to her like a shot.
She now has an amazing network of friends all over the country.
Admittedly none of us co-owned her house, and at times we didn't like her rules, but things always got ironed out in the end. In many ways it was like a marriage, that period of adjustment to each other to start with, although it was also like being young again and finding that your flatmate was always nicking your clothes...