Mother and Son Living Together

I am divorced and my children are grown up. I live alone in an apartment. My parents divorced a long time ago and my mother lives by herself in another apartment a few blocks away. Besides my mother, I have no family nearby. My mother and I could save money by sharing an apartment. Neither of us ever plan to marry again. My mother still works, but she probably will retire within the next few years. Is it permitted under Jewish law for a mother and adult son to live together?